diff --git a/nisystemlink/clients/spec/models/__init__.py b/nisystemlink/clients/spec/models/__init__.py
index b30499ec..7656ced6 100644
--- a/nisystemlink/clients/spec/models/__init__.py
+++ b/nisystemlink/clients/spec/models/__init__.py
@@ -16,6 +16,7 @@
 from ._query_specs import (
     QuerySpecificationsRequest,
     PagedSpecifications,
+    SpecificationOrderBy,
     SpecificationProjection,
 )
 from ._specification import (
diff --git a/nisystemlink/clients/spec/models/_query_specs.py b/nisystemlink/clients/spec/models/_query_specs.py
index 1d827b99..024739fa 100644
--- a/nisystemlink/clients/spec/models/_query_specs.py
+++ b/nisystemlink/clients/spec/models/_query_specs.py
@@ -32,6 +32,7 @@ class SpecificationProjection(str, Enum):
     WORKSPACE = "WORKSPACE"
     CREATED_AT = "CREATED_AT"
     CREATED_BY = "CREATED_BY"
+    UPDATED_AT = "UPDATED_AT"
 
 
 class SpecificationOrderBy(Enum):
@@ -39,6 +40,7 @@ class SpecificationOrderBy(Enum):
 
     ID = "ID"
     SPEC_ID = "SPEC_ID"
+    UPDATED_AT = "UPDATED_AT"
 
 
 class QuerySpecificationsRequest(JsonModel):
diff --git a/tests/integration/spec/test_spec.py b/tests/integration/spec/test_spec.py
index a1c0d470..d9cff32d 100644
--- a/tests/integration/spec/test_spec.py
+++ b/tests/integration/spec/test_spec.py
@@ -16,6 +16,7 @@
     NumericConditionValue,
     QuerySpecificationsRequest,
     SpecificationLimit,
+    SpecificationOrderBy,
     SpecificationProjection,
     SpecificationType,
     StringConditionValue,
@@ -318,7 +319,11 @@ def test__query_spec_projection_columns__columns_returned(
     ):
         request = QuerySpecificationsRequest(
             product_ids=[product],
-            projection=[SpecificationProjection.SPEC_ID, SpecificationProjection.NAME],
+            projection=[
+                SpecificationProjection.SPEC_ID,
+                SpecificationProjection.NAME,
+                SpecificationProjection.UPDATED_AT,
+            ],
         )
 
         response = client.query_specs(request)
@@ -329,9 +334,10 @@ def test__query_spec_projection_columns__columns_returned(
 
         assert response.specs
         assert len(response.specs) == 3
-        assert len(spec_columns) == 2
+        assert len(spec_columns) == 3
         assert "spec_id" in spec_columns
         assert "name" in spec_columns
+        assert "updated_at" in spec_columns
 
     def test__query_specs__returns_condition_value_type_correctly(
         self, client: SpecClient, create_specs, create_specs_for_query, product
@@ -405,3 +411,71 @@ def test__without_condition_type_projection__query_specs__condition_type_field_i
         assert "condition_name" in spec_columns
         assert "condition_unit" in spec_columns
         assert "condition_type" not in spec_columns
+
+    @pytest.mark.parametrize(
+        "order_by_descending, expected_first, expected_second",
+        [
+            (False, "spec_2_id", "spec_1_id"),
+            (True, "spec_1_id", "spec_2_id"),
+        ],
+    )
+    def test__query_specs_order_by_updated_at__returns_in_expected_order(
+        self,
+        client: SpecClient,
+        create_specs,
+        product,
+        order_by_descending: bool,
+        expected_first: str,
+        expected_second: str,
+    ):
+        # Create two specs, then update the first so it has a later updated_at than the second.
+        spec_1_id = uuid.uuid1().hex
+        spec_2_id = uuid.uuid1().hex
+        response = create_specs(
+            CreateSpecificationsRequest(
+                specs=[
+                    CreateSpecificationsRequestObject(
+                        product_id=product,
+                        spec_id=spec_1_id,
+                        type=SpecificationType.FUNCTIONAL,
+                    ),
+                    CreateSpecificationsRequestObject(
+                        product_id=product,
+                        spec_id=spec_2_id,
+                        type=SpecificationType.FUNCTIONAL,
+                    ),
+                ]
+            )
+        )
+        spec_1 = next(
+            spec for spec in response.created_specs if spec.spec_id == spec_1_id
+        )
+        update_response = client.update_specs(
+            UpdateSpecificationsRequest(
+                specs=[
+                    UpdateSpecificationsRequestObject(
+                        id=spec_1.id,
+                        product_id=spec_1.product_id,
+                        spec_id=spec_1.spec_id,
+                        type=SpecificationType.PARAMETRIC,
+                        version=spec_1.version,
+                        workspace=spec_1.workspace,
+                    )
+                ]
+            )
+        )
+        assert update_response
+        assert update_response.updated_specs
+        assert len(update_response.updated_specs) == 1
+
+        request = QuerySpecificationsRequest(
+            product_ids=[product],
+            order_by=SpecificationOrderBy.UPDATED_AT,
+            order_by_descending=order_by_descending,
+        )
+        response = client.query_specs(request)
+
+        ids = {"spec_1_id": spec_1_id, "spec_2_id": spec_2_id}
+        assert response.specs
+        assert response.specs[0].spec_id == ids[expected_first]
+        assert response.specs[1].spec_id == ids[expected_second]