diff --git a/tests/unit/test_client.py b/tests/unit/test_client.py
new file mode 100644
index 0000000..e765ba0
--- /dev/null
+++ b/tests/unit/test_client.py
@@ -0,0 +1,129 @@
+# Copyright (c) Microsoft Corporation.
+# Licensed under the MIT license.
+
+import unittest
+from unittest.mock import MagicMock
+
+from azure.core.credentials import TokenCredential
+
+from PowerPlatform.Dataverse.client import DataverseClient
+
+
+class TestDataverseClient(unittest.TestCase):
+    def setUp(self):
+        """Set up test fixtures before each test method."""
+        # Create mock credential
+        self.mock_credential = MagicMock(spec=TokenCredential)
+        self.base_url = "https://example.crm.dynamics.com"
+
+        # Initialize the client under test
+        self.client = DataverseClient(self.base_url, self.mock_credential)
+
+        # Mock the internal _odata client
+        # This ensures we verify logic without making actual HTTP calls
+        self.client._odata = MagicMock()
+
+    def test_create_single(self):
+        """Test create method with a single record."""
+        # Setup mock return values
+        # _create must return a GUID string
+        self.client._odata._create.return_value = "00000000-0000-0000-0000-000000000000"
+        # _entity_set_from_schema_name should return the plural entity set name
+        self.client._odata._entity_set_from_schema_name.return_value = "accounts"
+
+        # Execute test
+        self.client.create("account", {"name": "Contoso Ltd"})
+
+        # Verify
+        # Ensure _entity_set_from_schema_name was called and its result ("accounts") was passed to _create
+        self.client._odata._create.assert_called_once_with("accounts", "account", {"name": "Contoso Ltd"})
+
+    def test_create_multiple(self):
+        """Test create method with multiple records."""
+        payloads = [{"name": "Company A"}, {"name": "Company B"}, {"name": "Company C"}]
+
+        # Setup mock return values
+        # _create_multiple must return a list of GUID strings
+        self.client._odata._create_multiple.return_value = [
+            "00000000-0000-0000-0000-000000000001",
+            "00000000-0000-0000-0000-000000000002",
+            "00000000-0000-0000-0000-000000000003",
+        ]
+        self.client._odata._entity_set_from_schema_name.return_value = "accounts"
+
+        # Execute test
+        self.client.create("account", payloads)
+
+        # Verify
+        self.client._odata._create_multiple.assert_called_once_with("accounts", "account", payloads)
+
+    def test_update_single(self):
+        """Test update method with a single record."""
+        self.client.update("account", "00000000-0000-0000-0000-000000000000", {"telephone1": "555-0199"})
+        self.client._odata._update.assert_called_once_with(
+            "account", "00000000-0000-0000-0000-000000000000", {"telephone1": "555-0199"}
+        )
+
+    def test_update_multiple(self):
+        """Test update method with multiple records (broadcast)."""
+        ids = [
+            "00000000-0000-0000-0000-000000000001",
+            "00000000-0000-0000-0000-000000000002",
+        ]
+        changes = {"statecode": 1}
+
+        self.client.update("account", ids, changes)
+        self.client._odata._update_by_ids.assert_called_once_with("account", ids, changes)
+
+    def test_delete_single(self):
+        """Test delete method with a single record."""
+        self.client.delete("account", "00000000-0000-0000-0000-000000000000")
+        self.client._odata._delete.assert_called_once_with("account", "00000000-0000-0000-0000-000000000000")
+
+    def test_delete_multiple(self):
+        """Test delete method with multiple records."""
+        ids = [
+            "00000000-0000-0000-0000-000000000001",
+            "00000000-0000-0000-0000-000000000002",
+        ]
+        # Mock return value for bulk delete job ID
+        self.client._odata._delete_multiple.return_value = "job-guid-123"
+
+        job_id = self.client.delete("account", ids)
+
+        self.client._odata._delete_multiple.assert_called_once_with("account", ids)
+        self.assertEqual(job_id, "job-guid-123")
+
+    def test_get_single(self):
+        """Test get method with a single record ID."""
+        # Setup mock return value
+        expected_record = {"accountid": "00000000-0000-0000-0000-000000000000", "name": "Contoso"}
+        self.client._odata._get.return_value = expected_record
+
+        result = self.client.get("account", "00000000-0000-0000-0000-000000000000")
+
+        self.client._odata._get.assert_called_once_with("account", "00000000-0000-0000-0000-000000000000", select=None)
+        self.assertEqual(result, expected_record)
+
+    def test_get_multiple(self):
+        """Test get method for querying multiple records."""
+        # Setup mock return value (iterator)
+        expected_batch = [{"accountid": "1", "name": "A"}, {"accountid": "2", "name": "B"}]
+        self.client._odata._get_multiple.return_value = iter([expected_batch])
+
+        # Execute query
+        result_iterator = self.client.get("account", filter="statecode eq 0", top=10)
+
+        # Consume iterator to verify content
+        results = list(result_iterator)
+
+        self.client._odata._get_multiple.assert_called_once_with(
+            "account",
+            select=None,
+            filter="statecode eq 0",
+            orderby=None,
+            top=10,
+            expand=None,
+            page_size=None,
+        )
+        self.assertEqual(results, [expected_batch])