diff --git a/.gitignore b/.gitignore
index 57cc36e..3ffe6c7 100644
--- a/.gitignore
+++ b/.gitignore
@@ -21,4 +21,42 @@ environments/dataset/data/sorting/2_boxes/*
 environments/dataset/data/sorting/4_boxes/*
 environments/dataset/data/sorting/6_boxes/*
 environments/dataset/data/stacking/all_data/*
-environments/dataset/data/stacking/vision_data/*
\ No newline at end of file
+environments/dataset/data/stacking/vision_data/*
+
+# Testing and Coverage
+.pytest_cache/
+.coverage
+htmlcov/
+coverage.xml
+.tox/
+.cache/
+nosetests.xml
+coverage/
+*.cover
+.hypothesis/
+
+# Claude settings
+.claude/*
+
+# Virtual environments
+venv/
+env/
+.venv/
+.env/
+ENV/
+env.bak/
+venv.bak/
+
+# IDE files
+.vscode/
+*.sublime-project
+*.sublime-workspace
+
+# OS files
+.DS_Store
+Thumbs.db
+
+# Build artifacts
+build/
+dist/
+*.egg-info/
\ No newline at end of file
diff --git a/poetry.lock b/poetry.lock
new file mode 100644
index 0000000..6e20ed5
--- /dev/null
+++ b/poetry.lock
@@ -0,0 +1,282 @@
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+
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+
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+]
+
+[package.extras]
+dev = ["pre-commit", "tox"]
+testing = ["pytest", "pytest-benchmark"]
+
+[[package]]
+name = "pytest"
+version = "7.4.4"
+description = "pytest: simple powerful testing with Python"
+optional = false
+python-versions = ">=3.7"
+groups = ["test"]
+files = [
+    {file = "pytest-7.4.4-py3-none-any.whl", hash = "sha256:b090cdf5ed60bf4c45261be03239c2c1c22df034fbffe691abe93cd80cea01d8"},
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+]
+
+[package.dependencies]
+colorama = {version = "*", markers = "sys_platform == \"win32\""}
+exceptiongroup = {version = ">=1.0.0rc8", markers = "python_version < \"3.11\""}
+iniconfig = "*"
+packaging = "*"
+pluggy = ">=0.12,<2.0"
+tomli = {version = ">=1.0.0", markers = "python_version < \"3.11\""}
+
+[package.extras]
+testing = ["argcomplete", "attrs (>=19.2.0)", "hypothesis (>=3.56)", "mock", "nose", "pygments (>=2.7.2)", "requests", "setuptools", "xmlschema"]
+
+[[package]]
+name = "pytest-cov"
+version = "4.1.0"
+description = "Pytest plugin for measuring coverage."
+optional = false
+python-versions = ">=3.7"
+groups = ["test"]
+files = [
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+]
+
+[package.dependencies]
+coverage = {version = ">=5.2.1", extras = ["toml"]}
+pytest = ">=4.6"
+
+[package.extras]
+testing = ["fields", "hunter", "process-tests", "pytest-xdist", "six", "virtualenv"]
+
+[[package]]
+name = "pytest-mock"
+version = "3.14.1"
+description = "Thin-wrapper around the mock package for easier use with pytest"
+optional = false
+python-versions = ">=3.8"
+groups = ["test"]
+files = [
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+]
+
+[package.dependencies]
+pytest = ">=6.2.5"
+
+[package.extras]
+dev = ["pre-commit", "pytest-asyncio", "tox"]
+
+[[package]]
+name = "tomli"
+version = "2.2.1"
+description = "A lil' TOML parser"
+optional = false
+python-versions = ">=3.8"
+groups = ["test"]
+markers = "python_full_version <= \"3.11.0a6\""
+files = [
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+    {file = "tomli-2.2.1-py3-none-any.whl", hash = "sha256:cb55c73c5f4408779d0cf3eef9f762b9c9f147a77de7b258bef0a5628adc85cc"},
+    {file = "tomli-2.2.1.tar.gz", hash = "sha256:cd45e1dc79c835ce60f7404ec8119f2eb06d38b1deba146f07ced3bbc44505ff"},
+]
+
+[[package]]
+name = "typing-extensions"
+version = "4.13.2"
+description = "Backported and Experimental Type Hints for Python 3.8+"
+optional = false
+python-versions = ">=3.8"
+groups = ["test"]
+markers = "python_version < \"3.11\""
+files = [
+    {file = "typing_extensions-4.13.2-py3-none-any.whl", hash = "sha256:a439e7c04b49fec3e5d3e2beaa21755cadbbdc391694e28ccdd36ca4a1408f8c"},
+    {file = "typing_extensions-4.13.2.tar.gz", hash = "sha256:e6c81219bd689f51865d9e372991c540bda33a0379d5573cddb9a3a23f7caaef"},
+]
+
+[metadata]
+lock-version = "2.1"
+python-versions = "^3.8"
+content-hash = "308097793916ecb89df2fba7feb4c5e54a83de2d564f628aedacae41dc1149ee"
diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 0000000..bb835e9
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,81 @@
+[build-system]
+requires = ["poetry-core"]
+build-backend = "poetry.core.masonry.api"
+
+[tool.poetry]
+name = "behaviour-cloning-benchmarks"
+version = "0.1.0"
+description = "A comprehensive benchmarking framework for behaviour cloning algorithms"
+authors = ["Your Name <your.email@example.com>"]
+readme = "README.md"
+packages = [{include = "agents"}, {include = "environments"}, {include = "simulation"}]
+
+[tool.poetry.dependencies]
+python = "^3.8"
+# Add production dependencies here as needed
+
+[tool.poetry.group.test.dependencies]
+pytest = "^7.4.0"
+pytest-cov = "^4.1.0"
+pytest-mock = "^3.11.1"
+
+[tool.poetry.scripts]
+test = "pytest:main"
+tests = "pytest:main"
+
+[tool.pytest.ini_options]
+testpaths = ["tests"]
+python_files = ["test_*.py", "*_test.py"]
+python_classes = ["Test*"]
+python_functions = ["test_*"]
+addopts = [
+    "--strict-markers",
+    "--strict-config",
+    "--verbose",
+    "--cov=agents",
+    "--cov=environments", 
+    "--cov=simulation",
+    "--cov-report=term-missing",
+    "--cov-report=html:htmlcov",
+    "--cov-report=xml:coverage.xml",
+    "--cov-fail-under=80"
+]
+markers = [
+    "unit: Unit tests",
+    "integration: Integration tests", 
+    "slow: Slow running tests"
+]
+
+[tool.coverage.run]
+source = ["agents", "environments", "simulation"]
+omit = [
+    "*/tests/*",
+    "*/test_*",
+    "*/__pycache__/*",
+    "*/venv/*",
+    "*/env/*",
+    "*/.venv/*",
+    "*/.env/*",
+    "*/setup.py",
+    "*/conftest.py",
+    "*/__init__.py"
+]
+
+[tool.coverage.report]
+exclude_lines = [
+    "pragma: no cover",
+    "def __repr__",
+    "if self.debug:",
+    "if settings.DEBUG",
+    "raise AssertionError",
+    "raise NotImplementedError",
+    "if 0:",
+    "if __name__ == .__main__.:",
+    "class .*\\bProtocol\\):",
+    "@(abc\\.)?abstractmethod"
+]
+show_missing = true
+precision = 2
+
+[tool.coverage.html]
+directory = "htmlcov"
\ No newline at end of file
diff --git a/tests/__init__.py b/tests/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/tests/conftest.py b/tests/conftest.py
new file mode 100644
index 0000000..b27d257
--- /dev/null
+++ b/tests/conftest.py
@@ -0,0 +1,227 @@
+"""
+Shared pytest fixtures for the behaviour cloning benchmarks test suite.
+"""
+import os
+import tempfile
+import shutil
+from pathlib import Path
+from typing import Dict, Any, Generator
+import pytest
+from unittest.mock import Mock, MagicMock
+
+
+@pytest.fixture
+def temp_dir() -> Generator[Path, None, None]:
+    """
+    Create a temporary directory that is automatically cleaned up after the test.
+    
+    Returns:
+        Path: Path to the temporary directory
+    """
+    temp_path = Path(tempfile.mkdtemp())
+    try:
+        yield temp_path
+    finally:
+        shutil.rmtree(temp_path, ignore_errors=True)
+
+
+@pytest.fixture
+def temp_file(temp_dir: Path) -> Path:
+    """
+    Create a temporary file within a temporary directory.
+    
+    Args:
+        temp_dir: The temporary directory fixture
+        
+    Returns:
+        Path: Path to the temporary file
+    """
+    temp_file = temp_dir / "test_file.txt"
+    temp_file.write_text("test content")
+    return temp_file
+
+
+@pytest.fixture
+def mock_config() -> Dict[str, Any]:
+    """
+    Mock configuration dictionary for testing.
+    
+    Returns:
+        Dict: Mock configuration with common test values
+    """
+    return {
+        "model": {
+            "name": "test_model",
+            "hidden_dim": 128,
+            "num_layers": 2,
+        },
+        "training": {
+            "batch_size": 32,
+            "learning_rate": 0.001,
+            "num_epochs": 10,
+        },
+        "data": {
+            "sequence_length": 100,
+            "normalize": True,
+        },
+        "environment": {
+            "name": "test_env",
+            "max_steps": 1000,
+        }
+    }
+
+
+@pytest.fixture
+def mock_device():
+    """
+    Mock device for testing (CPU/CUDA agnostic).
+    
+    Returns:
+        str: Mock device string
+    """
+    return "cpu"
+
+
+@pytest.fixture
+def mock_agent():
+    """
+    Mock agent for testing agent functionality.
+    
+    Returns:
+        Mock: Mock agent with common methods
+    """
+    agent = MagicMock()
+    agent.predict.return_value = [0.5, 0.3, 0.2]  # Mock action
+    agent.train.return_value = {"loss": 0.1, "accuracy": 0.95}
+    agent.save.return_value = True
+    agent.load.return_value = True
+    return agent
+
+
+@pytest.fixture
+def mock_dataset():
+    """
+    Mock dataset for testing data loading functionality.
+    
+    Returns:
+        Mock: Mock dataset with common methods
+    """
+    dataset = MagicMock()
+    dataset.__len__.return_value = 100
+    dataset.__getitem__.return_value = {
+        "observations": [1.0, 2.0, 3.0],
+        "actions": [0.1, 0.2, 0.3],
+        "rewards": 1.0
+    }
+    return dataset
+
+
+@pytest.fixture
+def mock_environment():
+    """
+    Mock environment for testing simulation functionality.
+    
+    Returns:
+        Mock: Mock environment with gym-like interface
+    """
+    env = MagicMock()
+    env.reset.return_value = [0.0, 0.0, 0.0]  # Mock observation
+    env.step.return_value = ([0.1, 0.1, 0.1], 1.0, False, {})  # obs, reward, done, info
+    env.close.return_value = None
+    return env
+
+
+@pytest.fixture
+def sample_observation():
+    """
+    Sample observation data for testing.
+    
+    Returns:
+        list: Sample observation vector
+    """
+    return [0.1, 0.2, 0.3, 0.4, 0.5]
+
+
+@pytest.fixture
+def sample_action():
+    """
+    Sample action data for testing.
+    
+    Returns:
+        list: Sample action vector
+    """
+    return [0.0, 1.0, 0.0]
+
+
+@pytest.fixture(scope="session")
+def test_data_dir() -> Path:
+    """
+    Directory containing test data files.
+    
+    Returns:
+        Path: Path to test data directory
+    """
+    return Path(__file__).parent / "data"
+
+
+@pytest.fixture
+def clean_environment():
+    """
+    Clean environment variables for testing.
+    Saves and restores environment state.
+    """
+    old_environ = dict(os.environ)
+    # Clear potentially interfering environment variables
+    test_vars_to_clear = [
+        "CUDA_VISIBLE_DEVICES",
+        "PYTHONPATH",
+    ]
+    
+    for var in test_vars_to_clear:
+        os.environ.pop(var, None)
+    
+    try:
+        yield
+    finally:
+        os.environ.clear()
+        os.environ.update(old_environ)
+
+
+@pytest.fixture
+def disable_gpu():
+    """
+    Force CPU-only mode for testing.
+    """
+    old_environ = dict(os.environ)
+    os.environ["CUDA_VISIBLE_DEVICES"] = ""
+    
+    try:
+        yield
+    finally:
+        os.environ.clear()
+        os.environ.update(old_environ)
+
+
+# Pytest configuration hooks
+def pytest_configure(config):
+    """Configure pytest with custom markers."""
+    config.addinivalue_line(
+        "markers", "unit: mark test as a unit test"
+    )
+    config.addinivalue_line(
+        "markers", "integration: mark test as an integration test"
+    )
+    config.addinivalue_line(
+        "markers", "slow: mark test as slow running"
+    )
+
+
+def pytest_collection_modifyitems(config, items):
+    """Automatically mark tests based on their location."""
+    for item in items:
+        # Mark tests in unit/ directory as unit tests
+        if "unit" in str(item.fspath):
+            item.add_marker(pytest.mark.unit)
+        # Mark tests in integration/ directory as integration tests
+        elif "integration" in str(item.fspath):
+            item.add_marker(pytest.mark.integration)
\ No newline at end of file
diff --git a/tests/integration/__init__.py b/tests/integration/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/tests/integration/test_sample_integration.py b/tests/integration/test_sample_integration.py
new file mode 100644
index 0000000..47416d7
--- /dev/null
+++ b/tests/integration/test_sample_integration.py
@@ -0,0 +1,25 @@
+"""
+Sample integration test to demonstrate integration test structure.
+"""
+import pytest
+
+
+@pytest.mark.integration  
+class TestSampleIntegration:
+    """Sample integration test class."""
+    
+    def test_basic_integration(self):
+        """Basic integration test."""
+        assert True
+        
+    def test_with_multiple_fixtures(self, mock_agent, mock_environment):
+        """Integration test using multiple fixtures."""
+        # Simulate agent interacting with environment
+        obs = mock_environment.reset()
+        action = mock_agent.predict(obs)
+        next_obs, reward, done, info = mock_environment.step(action)
+        
+        assert obs == [0.0, 0.0, 0.0]
+        assert action == [0.5, 0.3, 0.2]
+        assert next_obs == [0.1, 0.1, 0.1]
+        assert reward == 1.0
\ No newline at end of file
diff --git a/tests/test_infrastructure.py b/tests/test_infrastructure.py
new file mode 100644
index 0000000..8ca7272
--- /dev/null
+++ b/tests/test_infrastructure.py
@@ -0,0 +1,154 @@
+"""
+Infrastructure validation tests to ensure the testing setup works correctly.
+"""
+import pytest
+from pathlib import Path
+import tempfile
+import os
+
+
+class TestInfrastructure:
+    """Test class to validate testing infrastructure setup."""
+    
+    def test_pytest_working(self):
+        """Test that pytest is working correctly."""
+        assert True
+        
+    def test_temp_dir_fixture(self, temp_dir):
+        """Test that temp_dir fixture works."""
+        assert isinstance(temp_dir, Path)
+        assert temp_dir.exists()
+        assert temp_dir.is_dir()
+        
+    def test_temp_file_fixture(self, temp_file):
+        """Test that temp_file fixture works."""
+        assert isinstance(temp_file, Path)
+        assert temp_file.exists()
+        assert temp_file.is_file()
+        assert temp_file.read_text() == "test content"
+        
+    def test_mock_config_fixture(self, mock_config):
+        """Test that mock_config fixture works."""
+        assert isinstance(mock_config, dict)
+        assert "model" in mock_config
+        assert "training" in mock_config
+        assert "data" in mock_config
+        assert "environment" in mock_config
+        
+    def test_mock_agent_fixture(self, mock_agent):
+        """Test that mock_agent fixture works."""
+        # Test predict method
+        result = mock_agent.predict()
+        assert result == [0.5, 0.3, 0.2]
+        
+        # Test train method
+        train_result = mock_agent.train()
+        assert "loss" in train_result
+        assert "accuracy" in train_result
+        
+    def test_mock_dataset_fixture(self, mock_dataset):
+        """Test that mock_dataset fixture works."""
+        assert len(mock_dataset) == 100
+        item = mock_dataset[0]
+        assert "observations" in item
+        assert "actions" in item
+        assert "rewards" in item
+        
+    def test_mock_environment_fixture(self, mock_environment):
+        """Test that mock_environment fixture works."""
+        # Test reset
+        obs = mock_environment.reset()
+        assert obs == [0.0, 0.0, 0.0]
+        
+        # Test step
+        obs, reward, done, info = mock_environment.step([1.0])
+        assert obs == [0.1, 0.1, 0.1]
+        assert reward == 1.0
+        assert done is False
+        assert isinstance(info, dict)
+        
+    def test_sample_data_fixtures(self, sample_observation, sample_action):
+        """Test that sample data fixtures work."""
+        assert len(sample_observation) == 5
+        assert len(sample_action) == 3
+        
+    @pytest.mark.unit
+    def test_unit_marker(self):
+        """Test that unit marker works."""
+        assert True
+        
+    def test_clean_environment_fixture(self, clean_environment):
+        """Test that clean_environment fixture works."""
+        # This test just ensures the fixture doesn't break
+        assert True
+        
+    def test_disable_gpu_fixture(self, disable_gpu):
+        """Test that disable_gpu fixture works."""
+        # Should set CUDA_VISIBLE_DEVICES to empty string
+        assert os.environ.get("CUDA_VISIBLE_DEVICES") == ""
+
+
+class TestProjectStructure:
+    """Test that the project structure is set up correctly."""
+    
+    def test_tests_directory_exists(self):
+        """Test that tests directory exists."""
+        tests_dir = Path(__file__).parent
+        assert tests_dir.exists()
+        assert tests_dir.is_dir()
+        
+    def test_unit_directory_exists(self):
+        """Test that unit tests directory exists."""
+        unit_dir = Path(__file__).parent / "unit"
+        assert unit_dir.exists()
+        assert unit_dir.is_dir()
+        
+    def test_integration_directory_exists(self):
+        """Test that integration tests directory exists."""
+        integration_dir = Path(__file__).parent / "integration"
+        assert integration_dir.exists()
+        assert integration_dir.is_dir()
+        
+    def test_conftest_exists(self):
+        """Test that conftest.py exists."""
+        conftest = Path(__file__).parent / "conftest.py"
+        assert conftest.exists()
+        assert conftest.is_file()
+        
+    def test_init_files_exist(self):
+        """Test that __init__.py files exist in test directories."""
+        test_dirs = [
+            Path(__file__).parent,
+            Path(__file__).parent / "unit",
+            Path(__file__).parent / "integration"
+        ]
+        
+        for test_dir in test_dirs:
+            init_file = test_dir / "__init__.py"
+            assert init_file.exists(), f"Missing __init__.py in {test_dir}"
+
+
+class TestPytestConfiguration:
+    """Test that pytest configuration is working."""
+    
+    def test_markers_available(self):
+        """Test that custom markers are available."""
+        # This will be validated by pytest's marker detection
+        assert True
+        
+    def test_coverage_configured(self):
+        """Test that coverage is configured (indirect test)."""
+        # This test ensures we can run without coverage breaking
+        assert True
+
+
+@pytest.mark.slow
+class TestSlowMarker:
+    """Test class for slow tests marker."""
+    
+    def test_slow_test(self):
+        """Test that slow marker works."""
+        # This is a mock slow test
+        import time
+        time.sleep(0.1)  # Very short sleep for demo
+        assert True
\ No newline at end of file
diff --git a/tests/unit/__init__.py b/tests/unit/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/tests/unit/test_sample_unit.py b/tests/unit/test_sample_unit.py
new file mode 100644
index 0000000..d482aa8
--- /dev/null
+++ b/tests/unit/test_sample_unit.py
@@ -0,0 +1,18 @@
+"""
+Sample unit test to demonstrate unit test structure.
+"""
+import pytest
+
+
+@pytest.mark.unit
+class TestSampleUnit:
+    """Sample unit test class."""
+    
+    def test_basic_assertion(self):
+        """Basic unit test."""
+        assert 1 + 1 == 2
+        
+    def test_with_fixture(self, mock_config):
+        """Unit test using a fixture."""
+        assert mock_config["model"]["name"] == "test_model"
+        assert mock_config["training"]["batch_size"] == 32
\ No newline at end of file