diff --git a/pyrit/cli/_output.py b/pyrit/cli/_output.py
index 3580c8e5b6..507b14629f 100644
--- a/pyrit/cli/_output.py
+++ b/pyrit/cli/_output.py
@@ -284,7 +284,7 @@ async def print_scenario_result_async(*, result_dict: dict[str, Any]) -> None:
     Args:
         result_dict: ``ScenarioResult.to_dict()`` payload from the REST API.
     """
-    from pyrit.models.scenario_result import ScenarioResult
+    from pyrit.models import ScenarioResult
     from pyrit.output.scenario_result.pretty import PrettyScenarioResultMemoryPrinter
 
     scenario_result = ScenarioResult.from_dict(result_dict)
diff --git a/pyrit/memory/memory_models.py b/pyrit/memory/memory_models.py
index ab467c31a7..f3a20abdd4 100644
--- a/pyrit/memory/memory_models.py
+++ b/pyrit/memory/memory_models.py
@@ -55,7 +55,6 @@
     SeedSimulatedConversation,
     SeedType,
 )
-from pyrit.models.scenario_result import ScenarioRunState
 
 logger = logging.getLogger(__name__)
 
diff --git a/pyrit/models/__init__.py b/pyrit/models/__init__.py
index b5ffe6be7b..12da83e36b 100644
--- a/pyrit/models/__init__.py
+++ b/pyrit/models/__init__.py
@@ -21,12 +21,6 @@
 from typing import TYPE_CHECKING, Any
 
 from pyrit.common.deprecation import print_deprecation_message
-from pyrit.models.chat_message import (
-    ALLOWED_CHAT_MESSAGE_ROLES,
-    ChatMessage,
-    ChatMessagesDataset,
-)
-from pyrit.models.conversation_reference import ConversationReference, ConversationType
 from pyrit.models.conversation_stats import ConversationStats
 from pyrit.models.embeddings import EmbeddingData, EmbeddingResponse, EmbeddingSupport, EmbeddingUsageInformation
 from pyrit.models.harm_definition import HarmDefinition, ScaleDescription, get_all_harm_definitions
@@ -79,11 +73,18 @@
     group_message_pieces_into_conversations,
     sort_message_pieces,
 )
+from pyrit.models.messages.chat_message import (
+    ALLOWED_CHAT_MESSAGE_ROLES,
+    ChatMessage,
+    ChatMessagesDataset,
+    ToolCall,
+)
+from pyrit.models.messages.conversation_reference import ConversationReference, ConversationType
 from pyrit.models.question_answering import QuestionAnsweringDataset, QuestionAnsweringEntry, QuestionChoice
 from pyrit.models.results.attack_result import AttackOutcome, AttackResult, AttackResultT
+from pyrit.models.results.scenario_result import ScenarioIdentifier, ScenarioResult, ScenarioRunState
 from pyrit.models.results.strategy_result import StrategyResult, StrategyResultT
 from pyrit.models.retry_event import RetryEvent
-from pyrit.models.scenario_result import ScenarioIdentifier, ScenarioResult, ScenarioRunState
 from pyrit.models.score import Score, ScoreType, UnvalidatedScore
 
 # Seeds - import from new seeds submodule for forward compatibility
@@ -192,6 +193,7 @@
     "TARGET_EVAL_PARAM_FALLBACKS",
     "TARGET_EVAL_PARAMS",
     "TextDataTypeSerializer",
+    "ToolCall",
     "UnvalidatedScore",
     "validate_registry_name",
     "VideoPathDataTypeSerializer",
diff --git a/pyrit/models/attack_result.py b/pyrit/models/attack_result.py
deleted file mode 100644
index 19ab95a058..0000000000
--- a/pyrit/models/attack_result.py
+++ /dev/null
@@ -1,23 +0,0 @@
-# Copyright (c) Microsoft Corporation.
-# Licensed under the MIT license.
-
-"""
-Backward-compatibility shim.
-
-``AttackResult`` and ``AttackOutcome`` now live in ``pyrit.models.results``.
-Import from there (or from ``pyrit.models``) instead. This module re-exports the
-public names so existing ``from pyrit.models.attack_result import ...`` imports
-keep working.
-"""
-
-from typing import Any
-
-from pyrit.models.results import attack_result as _attack_result
-from pyrit.models.results.attack_result import AttackOutcome, AttackResult, AttackResultT
-
-
-def __getattr__(name: str) -> Any:
-    return getattr(_attack_result, name)
-
-
-__all__ = ["AttackOutcome", "AttackResult", "AttackResultT"]
diff --git a/pyrit/models/message.py b/pyrit/models/message.py
deleted file mode 100644
index 27936dc04a..0000000000
--- a/pyrit/models/message.py
+++ /dev/null
@@ -1,37 +0,0 @@
-# Copyright (c) Microsoft Corporation.
-# Licensed under the MIT license.
-
-"""
-Backward-compatibility shim.
-
-``Message`` and the conversation helpers now live in ``pyrit.models.messages``.
-Import from there (or from ``pyrit.models``) instead. This module re-exports the
-public names so existing ``from pyrit.models.message import ...`` imports keep
-working.
-"""
-
-from typing import Any
-
-from pyrit.models.messages import message as _message
-from pyrit.models.messages.conversations import (
-    construct_response_from_request,
-    flatten_to_message_pieces,
-    get_all_values,
-    group_conversation_message_pieces_by_sequence,
-    group_message_pieces_into_conversations,
-)
-from pyrit.models.messages.message import Message
-
-
-def __getattr__(name: str) -> Any:
-    return getattr(_message, name)
-
-
-__all__ = [
-    "Message",
-    "construct_response_from_request",
-    "flatten_to_message_pieces",
-    "get_all_values",
-    "group_conversation_message_pieces_by_sequence",
-    "group_message_pieces_into_conversations",
-]
diff --git a/pyrit/models/message_piece.py b/pyrit/models/message_piece.py
deleted file mode 100644
index b5d92f3036..0000000000
--- a/pyrit/models/message_piece.py
+++ /dev/null
@@ -1,22 +0,0 @@
-# Copyright (c) Microsoft Corporation.
-# Licensed under the MIT license.
-
-"""
-Backward-compatibility shim.
-
-``MessagePiece`` now lives in ``pyrit.models.messages``. Import from there (or
-from ``pyrit.models``) instead. This module re-exports the public names so
-existing ``from pyrit.models.message_piece import ...`` imports keep working.
-"""
-
-from typing import Any
-
-from pyrit.models.messages import message_piece as _message_piece
-from pyrit.models.messages.message_piece import MessagePiece, sort_message_pieces
-
-
-def __getattr__(name: str) -> Any:
-    return getattr(_message_piece, name)
-
-
-__all__ = ["MessagePiece", "sort_message_pieces"]
diff --git a/pyrit/models/messages/__init__.py b/pyrit/models/messages/__init__.py
index 58c9f1a63e..c18b2a0964 100644
--- a/pyrit/models/messages/__init__.py
+++ b/pyrit/models/messages/__init__.py
@@ -6,11 +6,21 @@
 
 - MessagePiece: A single piece of a message exchanged with a target.
 - Message: One request/response to a target, made up of one or more pieces.
+- ChatMessage: OpenAI-style wire shape consumed/emitted by prompt targets.
+- Conversation: Conversation-scoped metadata shared by every piece.
+- ConversationReference: Immutable reference to a conversation in an attack.
 - conversations: Free functions that operate on collections of messages/pieces.
 """
 
-from pyrit.models.messages.conversation import Conversation
+from pyrit.models.messages.chat_message import (
+    ALLOWED_CHAT_MESSAGE_ROLES,
+    ChatMessage,
+    ChatMessagesDataset,
+    ToolCall,
+)
+from pyrit.models.messages.conversation_reference import ConversationReference, ConversationType
 from pyrit.models.messages.conversations import (
+    Conversation,
     construct_response_from_request,
     flatten_to_message_pieces,
     get_all_values,
@@ -21,9 +31,15 @@
 from pyrit.models.messages.message_piece import MessagePiece, sort_message_pieces
 
 __all__ = [
+    "ALLOWED_CHAT_MESSAGE_ROLES",
+    "ChatMessage",
+    "ChatMessagesDataset",
     "Conversation",
+    "ConversationReference",
+    "ConversationType",
     "Message",
     "MessagePiece",
+    "ToolCall",
     "construct_response_from_request",
     "flatten_to_message_pieces",
     "get_all_values",
diff --git a/pyrit/models/chat_message.py b/pyrit/models/messages/chat_message.py
similarity index 65%
rename from pyrit/models/chat_message.py
rename to pyrit/models/messages/chat_message.py
index 99939704a5..57e2b0dbab 100644
--- a/pyrit/models/chat_message.py
+++ b/pyrit/models/messages/chat_message.py
@@ -1,6 +1,20 @@
 # Copyright (c) Microsoft Corporation.
 # Licensed under the MIT license.
 
+"""
+OpenAI-format chat message types.
+
+``ChatMessage`` is the OpenAI Chat Completions wire shape — a ``role`` plus a
+string-or-multipart ``content``, with the OpenAI ``name`` / ``tool_calls`` /
+``tool_call_id`` fields. Prompt targets that speak the OpenAI API (and the many
+providers that mirror it) consume and emit these objects directly.
+
+It is intentionally distinct from the PyRIT domain ``Message`` / ``MessagePiece``
+types in this same package: those model a persisted request/response exchange,
+whereas ``ChatMessage`` is the lightweight OpenAI-shaped transport representation
+handed to a model API.
+"""
+
 from typing import Any
 
 from pydantic import BaseModel, ConfigDict
@@ -21,9 +35,9 @@ class ToolCall(BaseModel):
 
 class ChatMessage(BaseModel):
     """
-    Represents a chat message for API consumption.
+    Represents a single OpenAI Chat Completions message.
 
-    The content field can be:
+    Mirrors the OpenAI message schema. The content field can be:
     - A simple string for single-part text messages
     - A list of dicts for multipart messages (e.g., text + images)
     """
diff --git a/pyrit/models/messages/conversation.py b/pyrit/models/messages/conversation.py
deleted file mode 100644
index f5b8d956fb..0000000000
--- a/pyrit/models/messages/conversation.py
+++ /dev/null
@@ -1,31 +0,0 @@
-# Copyright (c) Microsoft Corporation.
-# Licensed under the MIT license.
-
-from __future__ import annotations
-
-from pydantic import BaseModel, ConfigDict
-
-from pyrit.models.score import (  # noqa: TC001  (runtime-required by Pydantic field annotations)
-    ComponentIdentifierField,
-)
-
-
-class Conversation(BaseModel):
-    """
-    Conversation-scoped metadata shared by every piece in a conversation.
-
-    A ``Conversation`` records identifiers that belong to the conversation as a
-    whole rather than to any individual ``MessagePiece`` -- most importantly the
-    target the conversation is held with. Persisting these once per conversation
-    (instead of stamping them onto every piece/row) is what keeps ``MessagePiece``
-    small.
-    """
-
-    model_config = ConfigDict(
-        arbitrary_types_allowed=True,
-        extra="forbid",
-        validate_assignment=False,
-    )
-
-    conversation_id: str
-    target_identifier: ComponentIdentifierField | None = None
diff --git a/pyrit/models/conversation_reference.py b/pyrit/models/messages/conversation_reference.py
similarity index 100%
rename from pyrit/models/conversation_reference.py
rename to pyrit/models/messages/conversation_reference.py
diff --git a/pyrit/models/messages/conversations.py b/pyrit/models/messages/conversations.py
index 9e829a28c8..d132679bb1 100644
--- a/pyrit/models/messages/conversations.py
+++ b/pyrit/models/messages/conversations.py
@@ -1,14 +1,19 @@
 # Copyright (c) Microsoft Corporation.
 # Licensed under the MIT license.
 
-"""Helpers that operate on collections of ``Message`` / ``MessagePiece``."""
+"""``Conversation`` model plus helpers that operate on collections of ``Message`` / ``MessagePiece``."""
 
 from __future__ import annotations
 
 from typing import TYPE_CHECKING
 
+from pydantic import BaseModel, ConfigDict
+
 from pyrit.models.messages.message import Message
 from pyrit.models.messages.message_piece import MessagePiece
+from pyrit.models.score import (  # noqa: TC001  (runtime-required by Pydantic field annotations)
+    ComponentIdentifierField,
+)
 
 if TYPE_CHECKING:
     from collections.abc import MutableSequence, Sequence
@@ -16,6 +21,27 @@
     from pyrit.models.literals import PromptDataType, PromptResponseError
 
 
+class Conversation(BaseModel):
+    """
+    Conversation-scoped metadata shared by every piece in a conversation.
+
+    A ``Conversation`` records identifiers that belong to the conversation as a
+    whole rather than to any individual ``MessagePiece`` -- most importantly the
+    target the conversation is held with. Persisting these once per conversation
+    (instead of stamping them onto every piece/row) is what keeps ``MessagePiece``
+    small.
+    """
+
+    model_config = ConfigDict(
+        arbitrary_types_allowed=True,
+        extra="forbid",
+        validate_assignment=False,
+    )
+
+    conversation_id: str
+    target_identifier: ComponentIdentifierField | None = None
+
+
 def get_all_values(messages: Sequence[Message]) -> list[str]:
     """
     Return all converted values across the provided messages.
diff --git a/pyrit/models/results/__init__.py b/pyrit/models/results/__init__.py
index 4bcc2f8848..b57cb1ef37 100644
--- a/pyrit/models/results/__init__.py
+++ b/pyrit/models/results/__init__.py
@@ -2,20 +2,31 @@
 # Licensed under the MIT license.
 
 """
-Results module - strategy and attack result types for PyRIT.
+Results module - strategy, attack, and scenario result types for PyRIT.
 
 - StrategyResult: Base class for all strategy results.
 - AttackResult: Result of an attack execution, with conversation/scoring evidence.
 - AttackOutcome: Enum of possible attack outcomes.
+- ScenarioResult: Aggregate result of a scenario run.
+- ScenarioIdentifier: Identifier describing the executed scenario.
+- ScenarioRunState: Lifecycle state of a scenario run.
 """
 
 from pyrit.models.results.attack_result import AttackOutcome, AttackResult, AttackResultT
+from pyrit.models.results.scenario_result import (
+    ScenarioIdentifier,
+    ScenarioResult,
+    ScenarioRunState,
+)
 from pyrit.models.results.strategy_result import StrategyResult, StrategyResultT
 
 __all__ = [
     "AttackOutcome",
     "AttackResult",
     "AttackResultT",
+    "ScenarioIdentifier",
+    "ScenarioResult",
+    "ScenarioRunState",
     "StrategyResult",
     "StrategyResultT",
 ]
diff --git a/pyrit/models/results/attack_result.py b/pyrit/models/results/attack_result.py
index 648c837214..138d3dd38e 100644
--- a/pyrit/models/results/attack_result.py
+++ b/pyrit/models/results/attack_result.py
@@ -11,8 +11,8 @@
 from pydantic import AwareDatetime, Field
 
 from pyrit.common.deprecation import print_deprecation_message
-from pyrit.models.conversation_reference import ConversationReference, ConversationType
 from pyrit.models.identifiers.component_identifier import ComponentIdentifier
+from pyrit.models.messages.conversation_reference import ConversationReference, ConversationType
 from pyrit.models.messages.message_piece import MessagePiece
 from pyrit.models.results.strategy_result import StrategyResult
 from pyrit.models.retry_event import RetryEvent
diff --git a/pyrit/models/scenario_result.py b/pyrit/models/results/scenario_result.py
similarity index 100%
rename from pyrit/models/scenario_result.py
rename to pyrit/models/results/scenario_result.py
diff --git a/pyrit/models/strategy_result.py b/pyrit/models/strategy_result.py
deleted file mode 100644
index bd4367695b..0000000000
--- a/pyrit/models/strategy_result.py
+++ /dev/null
@@ -1,22 +0,0 @@
-# Copyright (c) Microsoft Corporation.
-# Licensed under the MIT license.
-
-"""
-Backward-compatibility shim.
-
-``StrategyResult`` now lives in ``pyrit.models.results``. Import from there (or
-from ``pyrit.models``) instead. This module re-exports the public names so
-existing ``from pyrit.models.strategy_result import ...`` imports keep working.
-"""
-
-from typing import Any
-
-from pyrit.models.results import strategy_result as _strategy_result
-from pyrit.models.results.strategy_result import StrategyResult, StrategyResultT
-
-
-def __getattr__(name: str) -> Any:
-    return getattr(_strategy_result, name)
-
-
-__all__ = ["StrategyResult", "StrategyResultT"]
diff --git a/pyrit/output/helpers.py b/pyrit/output/helpers.py
index 87923d5862..c1a4b21b15 100644
--- a/pyrit/output/helpers.py
+++ b/pyrit/output/helpers.py
@@ -11,8 +11,7 @@
 
 import os
 
-from pyrit.models import AttackResult, ComponentIdentifier, Message, Score
-from pyrit.models.scenario_result import ScenarioResult
+from pyrit.models import AttackResult, ComponentIdentifier, Message, ScenarioResult, Score
 from pyrit.output.attack_result.markdown import MarkdownAttackResultMemoryPrinter
 from pyrit.output.attack_result.pretty import PrettyAttackResultMemoryPrinter
 from pyrit.output.conversation.pretty import PrettyConversationMemoryPrinter
diff --git a/pyrit/output/scenario_result/base.py b/pyrit/output/scenario_result/base.py
index 579d480acc..13972d9ac5 100644
--- a/pyrit/output/scenario_result/base.py
+++ b/pyrit/output/scenario_result/base.py
@@ -4,7 +4,7 @@
 from abc import abstractmethod
 
 from pyrit.common.deprecation import print_deprecation_message
-from pyrit.models.scenario_result import ScenarioResult
+from pyrit.models import ScenarioResult
 from pyrit.output.base import PrinterBase
 
 
diff --git a/pyrit/output/scenario_result/pretty.py b/pyrit/output/scenario_result/pretty.py
index 5abbc807ec..d8654c0bfd 100644
--- a/pyrit/output/scenario_result/pretty.py
+++ b/pyrit/output/scenario_result/pretty.py
@@ -6,8 +6,7 @@
 from colorama import Fore, Style
 
 from pyrit.common.deprecation import print_deprecation_message
-from pyrit.models import AttackOutcome
-from pyrit.models.scenario_result import ScenarioResult
+from pyrit.models import AttackOutcome, ScenarioResult
 from pyrit.output.scenario_result.base import ScenarioResultPrinterBase
 from pyrit.output.scorer.base import ScorerPrinterBase
 from pyrit.output.sink import Sink
diff --git a/pyrit/scenario/__init__.py b/pyrit/scenario/__init__.py
index a93f3098c1..2ef485abdf 100644
--- a/pyrit/scenario/__init__.py
+++ b/pyrit/scenario/__init__.py
@@ -19,7 +19,7 @@
 from types import ModuleType
 
 from pyrit.common.parameter import Parameter
-from pyrit.models.scenario_result import ScenarioIdentifier, ScenarioResult
+from pyrit.models import ScenarioIdentifier, ScenarioResult
 from pyrit.scenario.core import (
     AtomicAttack,
     AttackTechnique,
diff --git a/pyrit/scenario/core/scenario.py b/pyrit/scenario/core/scenario.py
index 4611128eda..dce77c3bbd 100644
--- a/pyrit/scenario/core/scenario.py
+++ b/pyrit/scenario/core/scenario.py
@@ -37,8 +37,14 @@
 from pyrit.executor.attack.single_turn.prompt_sending import PromptSendingAttack
 from pyrit.memory import CentralMemory
 from pyrit.memory.memory_models import ScenarioResultEntry
-from pyrit.models import AttackOutcome, AttackResult, SeedAttackGroup
-from pyrit.models.scenario_result import ScenarioIdentifier, ScenarioResult, ScenarioRunState
+from pyrit.models import (
+    AttackOutcome,
+    AttackResult,
+    ScenarioIdentifier,
+    ScenarioResult,
+    ScenarioRunState,
+    SeedAttackGroup,
+)
 from pyrit.prompt_target import PromptTarget
 from pyrit.prompt_target.common.target_requirements import TargetRequirements
 from pyrit.registry import ScorerRegistry
diff --git a/tests/partner_integration/azure_ai_evaluation/test_foundry_scenario_contract.py b/tests/partner_integration/azure_ai_evaluation/test_foundry_scenario_contract.py
index 3e806f03ef..4ff4d77b57 100644
--- a/tests/partner_integration/azure_ai_evaluation/test_foundry_scenario_contract.py
+++ b/tests/partner_integration/azure_ai_evaluation/test_foundry_scenario_contract.py
@@ -57,7 +57,7 @@ class TestScenarioResultContract:
 
     def test_scenario_result_importable(self):
         """ScenarioOrchestrator reads ScenarioResult."""
-        from pyrit.models.scenario_result import ScenarioResult
+        from pyrit.models import ScenarioResult
 
         assert ScenarioResult is not None
 
diff --git a/tests/unit/backend/test_attack_service.py b/tests/unit/backend/test_attack_service.py
index 2749c6fd67..5f7bee1809 100644
--- a/tests/unit/backend/test_attack_service.py
+++ b/tests/unit/backend/test_attack_service.py
@@ -1757,7 +1757,7 @@ async def test_conversation_summary_formats_media_preview(self, attack_service,
 
     async def test_returns_main_and_related_conversations(self, attack_service, mock_memory):
         """Should return main and PRUNED conversations sorted by timestamp."""
-        from pyrit.models.conversation_reference import ConversationReference, ConversationType
+        from pyrit.models import ConversationReference, ConversationType
 
         ar = make_attack_result(conversation_id="attack-1")
         ar.related_conversations.add(
@@ -1910,7 +1910,7 @@ async def test_raises_when_conversation_not_part_of_attack(self, attack_service,
 
     async def test_swaps_main_conversation(self, attack_service, mock_memory):
         """Changing the main to a related conversation should swap it with the main."""
-        from pyrit.models.conversation_reference import ConversationReference, ConversationType
+        from pyrit.models import ConversationReference, ConversationType
 
         ar = make_attack_result(conversation_id="attack-1")
         ar.related_conversations = {
@@ -1950,7 +1950,7 @@ class TestAddMessageTargetConversation:
     async def test_stores_message_in_target_conversation(self, attack_service, mock_memory):
         """When target_conversation_id is set, messages should go to that conversation."""
         from pyrit.backend.models.attacks import AttackSummary, ConversationMessagesResponse
-        from pyrit.models.conversation_reference import ConversationReference, ConversationType
+        from pyrit.models import ConversationReference, ConversationType
 
         ar = make_attack_result(conversation_id="attack-1")
         ar.related_conversations = {
@@ -2017,7 +2017,7 @@ class TestConversationCount:
 
     async def test_list_attacks_includes_related_conversation_ids(self, attack_service, mock_memory):
         """Attacks with related conversations should expose them in the summary."""
-        from pyrit.models.conversation_reference import ConversationReference, ConversationType
+        from pyrit.models import ConversationReference, ConversationType
 
         ar = make_attack_result(conversation_id="attack-1")
         ar.related_conversations = {
@@ -2069,7 +2069,7 @@ async def test_create_conversation_increments_count(self, attack_service, mock_m
     async def test_create_second_conversation_preserves_first(self, attack_service, mock_memory):
         """Creating a second related conversation should keep the first one."""
         from pyrit.backend.models.attacks import CreateConversationRequest
-        from pyrit.models.conversation_reference import ConversationReference, ConversationType
+        from pyrit.models import ConversationReference, ConversationType
 
         ar = make_attack_result(conversation_id="attack-1")
         ar.related_conversations = {
@@ -2099,7 +2099,7 @@ class TestConversationSorting:
 
     async def test_conversations_sorted_by_created_at_earliest_first(self, attack_service, mock_memory):
         """Conversations should be sorted by created_at with earliest first."""
-        from pyrit.models.conversation_reference import ConversationReference, ConversationType
+        from pyrit.models import ConversationReference, ConversationType
 
         ar = make_attack_result(conversation_id="attack-1")
         ar.related_conversations = {
@@ -2127,7 +2127,7 @@ async def test_conversations_sorted_by_created_at_earliest_first(self, attack_se
 
     async def test_empty_conversations_sorted_last(self, attack_service, mock_memory):
         """Conversations with no timestamp should appear at the bottom."""
-        from pyrit.models.conversation_reference import ConversationReference, ConversationType
+        from pyrit.models import ConversationReference, ConversationType
 
         ar = make_attack_result(conversation_id="attack-1")
         ar.related_conversations = {
@@ -2153,7 +2153,7 @@ async def test_empty_conversations_sorted_last(self, attack_service, mock_memory
 
     async def test_empty_conversations_all_sort_last(self, attack_service, mock_memory):
         """Multiple empty conversations should all have created_at=None."""
-        from pyrit.models.conversation_reference import ConversationReference, ConversationType
+        from pyrit.models import ConversationReference, ConversationType
 
         ar = make_attack_result(conversation_id="attack-1")
         ar.related_conversations = {
diff --git a/tests/unit/backend/test_mappers.py b/tests/unit/backend/test_mappers.py
index 9170f031df..1aba27d4b5 100644
--- a/tests/unit/backend/test_mappers.py
+++ b/tests/unit/backend/test_mappers.py
@@ -322,7 +322,7 @@ async def test_no_converters_returns_empty_list(self) -> None:
 
     async def test_related_conversation_ids_from_related_conversations(self) -> None:
         """Test that related_conversation_ids includes all related conversation IDs."""
-        from pyrit.models.conversation_reference import ConversationReference, ConversationType
+        from pyrit.models import ConversationReference, ConversationType
 
         ar = _make_attack_result()
         ar.related_conversations = {
diff --git a/tests/unit/backend/test_response_contracts.py b/tests/unit/backend/test_response_contracts.py
index bb7f403df3..15ff045b6a 100644
--- a/tests/unit/backend/test_response_contracts.py
+++ b/tests/unit/backend/test_response_contracts.py
@@ -24,12 +24,13 @@
 from pyrit.models import (
     AttackResult,
     ComponentIdentifier,
+    ConversationReference,
+    ConversationType,
     MessagePiece,
     RetryEvent,
     Score,
     build_atomic_attack_identifier,
 )
-from pyrit.models.conversation_reference import ConversationReference, ConversationType
 
 
 def _make_score() -> Score:
diff --git a/tests/unit/cli/test_output.py b/tests/unit/cli/test_output.py
index 26f41cccc2..b1c67cbbc6 100644
--- a/tests/unit/cli/test_output.py
+++ b/tests/unit/cli/test_output.py
@@ -319,7 +319,7 @@ async def test_print_scenario_result_async_uses_pretty_printer():
     fake_printer.write_async = AsyncMock()
 
     with (
-        patch("pyrit.models.scenario_result.ScenarioResult.from_dict", return_value=fake_scenario) as from_dict_mock,
+        patch("pyrit.models.ScenarioResult.from_dict", return_value=fake_scenario) as from_dict_mock,
         patch(
             "pyrit.output.scenario_result.pretty.PrettyScenarioResultMemoryPrinter", return_value=fake_printer
         ) as printer_cls,
@@ -339,8 +339,7 @@ async def test_print_scenario_result_async_roundtrip_with_real_payload():
     """
     from datetime import datetime, timezone
 
-    from pyrit.models import AttackOutcome, AttackResult, ComponentIdentifier
-    from pyrit.models.scenario_result import ScenarioIdentifier, ScenarioResult
+    from pyrit.models import AttackOutcome, AttackResult, ComponentIdentifier, ScenarioIdentifier, ScenarioResult
 
     identifier = ScenarioIdentifier(name="test.scenario", description="A test")
     target_identifier = ComponentIdentifier.from_dict(
diff --git a/tests/unit/models/test_attack_result.py b/tests/unit/models/test_attack_result.py
index 43e7522052..5b19316dfb 100644
--- a/tests/unit/models/test_attack_result.py
+++ b/tests/unit/models/test_attack_result.py
@@ -8,10 +8,8 @@
 import pytest
 
 from pyrit.memory.memory_models import AttackResultEntry
-from pyrit.models import ComponentIdentifier
-from pyrit.models.conversation_reference import ConversationReference, ConversationType
+from pyrit.models import AttackOutcome, AttackResult, ComponentIdentifier, ConversationReference, ConversationType
 from pyrit.models.messages.message_piece import MessagePiece
-from pyrit.models.results.attack_result import AttackOutcome, AttackResult
 from pyrit.models.retry_event import RetryEvent
 from pyrit.models.score import Score
 
@@ -393,24 +391,3 @@ def test_duplicate_preserves_subclass_type(self) -> None:
         assert copy.backtrack_count == 3
         copy.backtrack_count = 9
         assert original.backtrack_count == 3
-
-
-class TestAttackResultShim:
-    """The relocated module must be importable from the legacy path silently."""
-
-    def test_shim_reexports_same_classes_silently(self) -> None:
-        with warnings.catch_warnings(record=True) as caught:
-            warnings.simplefilter("always")
-            from pyrit.models.attack_result import AttackOutcome as ShimOutcome
-            from pyrit.models.attack_result import AttackResult as ShimResult
-
-        assert ShimResult is AttackResult
-        assert ShimOutcome is AttackOutcome
-        deprecation_warnings = [w for w in caught if issubclass(w.category, DeprecationWarning)]
-        assert len(deprecation_warnings) == 0, "Shim import must be silent"
-
-    def test_shim_getattr_reexports_dynamic_names(self) -> None:
-        """The module __getattr__ falls through to the relocated module."""
-        import pyrit.models.attack_result as shim
-
-        assert shim.AttackResultT is not None
diff --git a/tests/unit/models/test_chat_message.py b/tests/unit/models/test_chat_message.py
index c3475285b7..8fe206cf7e 100644
--- a/tests/unit/models/test_chat_message.py
+++ b/tests/unit/models/test_chat_message.py
@@ -6,11 +6,7 @@
 import pytest
 from pydantic import ValidationError
 
-from pyrit.models.chat_message import (
-    ChatMessage,
-    ChatMessagesDataset,
-    ToolCall,
-)
+from pyrit.models import ChatMessage, ChatMessagesDataset, ToolCall
 
 
 def test_tool_call_init():
diff --git a/tests/unit/models/test_conversation.py b/tests/unit/models/test_conversation.py
new file mode 100644
index 0000000000..b2576cd2e9
--- /dev/null
+++ b/tests/unit/models/test_conversation.py
@@ -0,0 +1,62 @@
+# Copyright (c) Microsoft Corporation.
+# Licensed under the MIT license.
+
+import pytest
+from pydantic import ValidationError
+
+from pyrit.models import ComponentIdentifier, Conversation
+
+
+def test_init_requires_conversation_id():
+    with pytest.raises(ValidationError):
+        Conversation()  # type: ignore[call-arg]
+
+
+def test_init_defaults_target_identifier_to_none():
+    conversation = Conversation(conversation_id="conv-1")
+    assert conversation.conversation_id == "conv-1"
+    assert conversation.target_identifier is None
+
+
+def test_init_forbids_extra_fields():
+    with pytest.raises(ValidationError):
+        Conversation(conversation_id="conv-1", unexpected="value")  # type: ignore[call-arg]
+
+
+def test_init_accepts_component_identifier():
+    identifier = ComponentIdentifier(class_name="OpenAIChatTarget", class_module="pyrit.prompt_target")
+    conversation = Conversation(conversation_id="conv-1", target_identifier=identifier)
+    assert conversation.target_identifier == identifier
+
+
+def test_target_identifier_accepts_flat_dict():
+    identifier = ComponentIdentifier(class_name="OpenAIChatTarget", class_module="pyrit.prompt_target")
+    conversation = Conversation(conversation_id="conv-1", target_identifier=identifier.model_dump())
+    assert isinstance(conversation.target_identifier, ComponentIdentifier)
+    assert conversation.target_identifier.class_name == "OpenAIChatTarget"
+
+
+def test_model_dump_serializes_target_identifier_to_flat_dict():
+    identifier = ComponentIdentifier(class_name="OpenAIChatTarget", class_module="pyrit.prompt_target")
+    conversation = Conversation(conversation_id="conv-1", target_identifier=identifier)
+
+    dumped = conversation.model_dump()
+
+    assert dumped["conversation_id"] == "conv-1"
+    assert dumped["target_identifier"]["class_name"] == "OpenAIChatTarget"
+    assert dumped["target_identifier"]["class_module"] == "pyrit.prompt_target"
+
+
+def test_model_dump_with_no_target_identifier():
+    conversation = Conversation(conversation_id="conv-1")
+    assert conversation.model_dump()["target_identifier"] is None
+
+
+def test_round_trips_through_model_validate():
+    identifier = ComponentIdentifier(class_name="OpenAIChatTarget", class_module="pyrit.prompt_target")
+    conversation = Conversation(conversation_id="conv-1", target_identifier=identifier)
+
+    restored = Conversation.model_validate(conversation.model_dump())
+
+    assert restored.conversation_id == "conv-1"
+    assert restored.target_identifier == identifier
diff --git a/tests/unit/models/test_conversation_reference.py b/tests/unit/models/test_conversation_reference.py
index de6263cd95..b229bc27eb 100644
--- a/tests/unit/models/test_conversation_reference.py
+++ b/tests/unit/models/test_conversation_reference.py
@@ -4,7 +4,7 @@
 import pytest
 from pydantic import ValidationError
 
-from pyrit.models.conversation_reference import ConversationReference, ConversationType
+from pyrit.models import ConversationReference, ConversationType
 
 
 def test_conversation_type_values():
diff --git a/tests/unit/models/test_message.py b/tests/unit/models/test_message.py
index 27468734f9..0d7913d4d3 100644
--- a/tests/unit/models/test_message.py
+++ b/tests/unit/models/test_message.py
@@ -462,12 +462,3 @@ def test_conversation_helpers_live_in_conversations_module(self) -> None:
             "construct_response_from_request",
         ):
             assert getattr(conversations, name) is getattr(messages, name)
-
-    def test_legacy_module_paths_reexport_same_objects(self) -> None:
-        import pyrit.models.message as legacy_message
-        import pyrit.models.message_piece as legacy_message_piece
-        from pyrit.models.messages.message import Message as PackagedMessage
-        from pyrit.models.messages.message_piece import MessagePiece as PackagedMessagePiece
-
-        assert legacy_message.Message is PackagedMessage
-        assert legacy_message_piece.MessagePiece is PackagedMessagePiece
diff --git a/tests/unit/models/test_scenario_result.py b/tests/unit/models/test_scenario_result.py
index e15abc53e7..ab2da79e8c 100644
--- a/tests/unit/models/test_scenario_result.py
+++ b/tests/unit/models/test_scenario_result.py
@@ -7,11 +7,15 @@
 import pytest
 
 import pyrit
-from pyrit.models import ComponentIdentifier
-from pyrit.models.conversation_reference import ConversationReference, ConversationType
+from pyrit.models import (
+    ComponentIdentifier,
+    ConversationReference,
+    ConversationType,
+    ScenarioIdentifier,
+    ScenarioResult,
+)
 from pyrit.models.results.attack_result import AttackOutcome, AttackResult
 from pyrit.models.retry_event import RetryEvent
-from pyrit.models.scenario_result import ScenarioIdentifier, ScenarioResult
 
 
 def _make_scenario_identifier(**kwargs):
diff --git a/tests/unit/models/test_strategy_result.py b/tests/unit/models/test_strategy_result.py
index 07508abef7..63d5a66c04 100644
--- a/tests/unit/models/test_strategy_result.py
+++ b/tests/unit/models/test_strategy_result.py
@@ -1,11 +1,9 @@
 # Copyright (c) Microsoft Corporation.
 # Licensed under the MIT license.
 
-import warnings
-
 import pytest
 
-from pyrit.models.results.strategy_result import StrategyResult
+from pyrit.models import StrategyResult
 
 
 class ConcreteResult(StrategyResult):
@@ -39,14 +37,3 @@ def test_strategy_result_duplicate_preserves_type():
 def test_strategy_result_forbids_extra_fields():
     with pytest.raises(ValueError):
         ConcreteResult(value="hello", count=1, unexpected="boom")
-
-
-def test_strategy_result_shim_reexports_same_class_silently():
-    """The old import path must re-export the identical class without warning."""
-    with warnings.catch_warnings(record=True) as caught:
-        warnings.simplefilter("always")
-        from pyrit.models.strategy_result import StrategyResult as ShimStrategyResult
-
-    assert ShimStrategyResult is StrategyResult
-    deprecation_warnings = [w for w in caught if issubclass(w.category, DeprecationWarning)]
-    assert len(deprecation_warnings) == 0, "Shim import must be silent"
diff --git a/tests/unit/output/attack_result/test_markdown.py b/tests/unit/output/attack_result/test_markdown.py
index b61081867a..7ce0c8b265 100644
--- a/tests/unit/output/attack_result/test_markdown.py
+++ b/tests/unit/output/attack_result/test_markdown.py
@@ -11,13 +11,13 @@
     AttackOutcome,
     AttackResult,
     ComponentIdentifier,
+    ConversationReference,
     ConversationType,
     Message,
     MessagePiece,
     Score,
     build_atomic_attack_identifier,
 )
-from pyrit.models.conversation_reference import ConversationReference
 from pyrit.output.attack_result.markdown import MarkdownAttackResultMemoryPrinter
 
 
diff --git a/tests/unit/output/attack_result/test_pretty.py b/tests/unit/output/attack_result/test_pretty.py
index dd7d02c6d7..7b9e79737d 100644
--- a/tests/unit/output/attack_result/test_pretty.py
+++ b/tests/unit/output/attack_result/test_pretty.py
@@ -10,13 +10,13 @@
     AttackOutcome,
     AttackResult,
     ComponentIdentifier,
+    ConversationReference,
     ConversationType,
     Message,
     MessagePiece,
     Score,
     build_atomic_attack_identifier,
 )
-from pyrit.models.conversation_reference import ConversationReference
 from pyrit.output.attack_result.pretty import PrettyAttackResultMemoryPrinter
 
 
diff --git a/tests/unit/output/scenario_result/test_base.py b/tests/unit/output/scenario_result/test_base.py
index fe64b39b2d..0d3bb06413 100644
--- a/tests/unit/output/scenario_result/test_base.py
+++ b/tests/unit/output/scenario_result/test_base.py
@@ -5,7 +5,7 @@
 
 import pytest
 
-from pyrit.models.scenario_result import ScenarioResult
+from pyrit.models import ScenarioResult
 from pyrit.output.scenario_result.base import ScenarioResultPrinterBase
 
 
diff --git a/tests/unit/output/scenario_result/test_pretty.py b/tests/unit/output/scenario_result/test_pretty.py
index b2f8cced9c..f1ba89c431 100644
--- a/tests/unit/output/scenario_result/test_pretty.py
+++ b/tests/unit/output/scenario_result/test_pretty.py
@@ -5,8 +5,7 @@
 
 import pytest
 
-from pyrit.models import AttackOutcome, AttackResult, ComponentIdentifier
-from pyrit.models.scenario_result import ScenarioIdentifier, ScenarioResult
+from pyrit.models import AttackOutcome, AttackResult, ComponentIdentifier, ScenarioIdentifier, ScenarioResult
 from pyrit.output.scenario_result.pretty import PrettyScenarioResultMemoryPrinter
 
 
diff --git a/tests/unit/scenario/core/test_scenario_parameters.py b/tests/unit/scenario/core/test_scenario_parameters.py
index 4a013f4365..17fee40f67 100644
--- a/tests/unit/scenario/core/test_scenario_parameters.py
+++ b/tests/unit/scenario/core/test_scenario_parameters.py
@@ -419,7 +419,7 @@ class TestResumeParameterValidation:
     @staticmethod
     def _make_stored_result(*, scenario_name: str, version: int, init_data):
         """Build a minimal ScenarioResult with a controlled identifier for resume tests."""
-        from pyrit.models.scenario_result import ScenarioIdentifier, ScenarioResult
+        from pyrit.models import ScenarioIdentifier, ScenarioResult
 
         identifier = ScenarioIdentifier(
             name=scenario_name,