diff --git a/pipeline/models.py b/pipeline/models.py
index d1daf00..65fc257 100644
--- a/pipeline/models.py
+++ b/pipeline/models.py
@@ -14,6 +14,7 @@
     validate_cohortextractor_outputs,
     validate_databuilder_outputs,
     validate_glob_pattern,
+    validate_no_kwargs,
     validate_type,
 )
 
@@ -58,6 +59,7 @@ def build(
         population_size: Any = None,
         **kwargs: Any,
     ) -> Expectations:
+        validate_no_kwargs(kwargs, "project `expectations` section")
         try:
             population_size = int(population_size)
         except (TypeError, ValueError):
@@ -91,6 +93,8 @@ def build(
                 f"must specify at least one output of: {', '.join(['highly_sensitive', 'moderately_sensitive', 'minimally_sensitive'])}"
             )
 
+        validate_no_kwargs(kwargs, f"`outputs` section for action {action_id}")
+
         cls.validate_output_filenames_are_valid(
             action_id, "highly_sensitive", highly_sensitive
         )
@@ -175,6 +179,7 @@ def build(
         dummy_data_file: Any = None,
         **kwargs: Any,
     ) -> Action:
+        validate_no_kwargs(kwargs, f"action {action_id}")
         validate_type(outputs, dict, f"`outputs` section for action {action_id}")
         validate_type(run, str, f"`run` section for action {action_id}")
         validate_type(
@@ -243,6 +248,7 @@ def build(
         expectations: Any = None,
         **kwargs: Any,
     ) -> Pipeline:
+        validate_no_kwargs(kwargs, "project")
         if version is None:
             raise ValidationError(
                 f"Project file must have a `version` attribute specifying which "
diff --git a/pipeline/validation.py b/pipeline/validation.py
index e8bd3de..d1cb2f2 100644
--- a/pipeline/validation.py
+++ b/pipeline/validation.py
@@ -25,6 +25,11 @@ def validate_type(val: Any, exp_type: type, loc: str, optional: bool = False) ->
         raise ValidationError(f"{loc} must be a {type_lookup[exp_type]}")
 
 
+def validate_no_kwargs(kwargs: dict[str, Any], loc: str) -> None:
+    if kwargs:
+        raise ValidationError(f"Unexpected parameters ({', '.join(kwargs)}) in {loc}")
+
+
 def validate_glob_pattern(pattern: str, privacy_level: str) -> None:
     """
     These patterns get converted into regular expressions and matched
diff --git a/tests/test_type_validation.py b/tests/test_type_validation.py
index c35e662..2ae5720 100644
--- a/tests/test_type_validation.py
+++ b/tests/test_type_validation.py
@@ -1,3 +1,5 @@
+import re
+
 import pytest
 
 from pipeline.exceptions import ValidationError
@@ -114,3 +116,61 @@ def test_output_filename_incorrect_type():
             },
             expectations={"population_size": 10},
         )
+
+
+def test_project_extra_parameters():
+    with pytest.raises(
+        ValidationError, match=re.escape("Unexpected parameters (extra) in project")
+    ):
+        Pipeline.build(extra=123)
+
+
+def test_action_extra_parameters():
+    with pytest.raises(
+        ValidationError,
+        match=re.escape("Unexpected parameters (extra) in action action1"),
+    ):
+        Pipeline.build(
+            version=3,
+            actions={
+                "action1": {
+                    "outputs": {},
+                    "run": "test:v1",
+                    "extra": 123,
+                }
+            },
+            expectations={"population_size": 10},
+        )
+
+
+def test_outputs_extra_parameters():
+    with pytest.raises(
+        ValidationError,
+        match=re.escape(
+            "Unexpected parameters (extra) in `outputs` section for action action1"
+        ),
+    ):
+        Pipeline.build(
+            version=3,
+            actions={
+                "action1": {
+                    "outputs": {"highly_sensitive": {"dataset": {}}, "extra": 123},
+                    "run": "test:v1",
+                }
+            },
+            expectations={"population_size": 10},
+        )
+
+
+def test_expectations_extra_parameters():
+    with pytest.raises(
+        ValidationError,
+        match=re.escape(
+            "Unexpected parameters (extra) in project `expectations` section"
+        ),
+    ):
+        Pipeline.build(
+            version=3,
+            actions={},
+            expectations={"population_size": 10, "extra": 123},
+        )