diff --git a/common/constants.cc b/common/constants.cc
index 25aa9a8..ac652ea 100644
--- a/common/constants.cc
+++ b/common/constants.cc
@@ -18,6 +18,8 @@
 
 namespace chromeos_update_engine {
 
+const char kExclusionPrefsSubDir[] = "exclusion";
+
 const char kDlcPrefsSubDir[] = "dlc";
 
 const char kPowerwashSafePrefsSubDirectory[] = "update_engine/prefs";
diff --git a/common/constants.h b/common/constants.h
index 67519bd..248fd05 100644
--- a/common/constants.h
+++ b/common/constants.h
@@ -19,6 +19,9 @@
 
 namespace chromeos_update_engine {
 
+// The root path of all exclusion prefs.
+extern const char kExclusionPrefsSubDir[];
+
 // The root path of all DLC metadata.
 extern const char kDlcPrefsSubDir[];
 
diff --git a/common/excluder_interface.h b/common/excluder_interface.h
new file mode 100644
index 0000000..3985bba
--- /dev/null
+++ b/common/excluder_interface.h
@@ -0,0 +1,60 @@
+//
+// Copyright (C) 2020 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_COMMON_EXCLUDER_INTERFACE_H_
+#define UPDATE_ENGINE_COMMON_EXCLUDER_INTERFACE_H_
+
+#include <memory>
+#include <string>
+
+#include <base/macros.h>
+
+namespace chromeos_update_engine {
+
+class PrefsInterface;
+
+class ExcluderInterface {
+ public:
+  virtual ~ExcluderInterface() = default;
+
+  // Returns true on successfuly excluding |name|, otherwise false. On a
+  // successful |Exclude()| the passed in |name| will be considered excluded
+  // and calls to |IsExcluded()| will return true. The exclusions are persisted.
+  virtual bool Exclude(const std::string& name) = 0;
+
+  // Returns true if |name| reached the exclusion limit, otherwise false.
+  virtual bool IsExcluded(const std::string& name) = 0;
+
+  // Returns true on sucessfully reseting the entire exclusion state, otherwise
+  // false. On a successful |Reset()| there will be no excluded |name| in the
+  // exclusion state.
+  virtual bool Reset() = 0;
+
+  // Not copyable or movable
+  ExcluderInterface(const ExcluderInterface&) = delete;
+  ExcluderInterface& operator=(const ExcluderInterface&) = delete;
+  ExcluderInterface(ExcluderInterface&&) = delete;
+  ExcluderInterface& operator=(ExcluderInterface&&) = delete;
+
+ protected:
+  ExcluderInterface() = default;
+};
+
+std::unique_ptr<ExcluderInterface> CreateExcluder(PrefsInterface* prefs);
+
+}  // namespace chromeos_update_engine
+
+#endif  // UPDATE_ENGINE_COMMON_EXCLUDER_INTERFACE_H_
diff --git a/common/excluder_stub.cc b/common/excluder_stub.cc
new file mode 100644
index 0000000..a251765
--- /dev/null
+++ b/common/excluder_stub.cc
@@ -0,0 +1,43 @@
+//
+// Copyright (C) 2020 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#include "update_engine/common/excluder_stub.h"
+
+#include <memory>
+
+#include "update_engine/common/prefs_interface.h"
+
+using std::string;
+
+namespace chromeos_update_engine {
+
+std::unique_ptr<ExcluderInterface> CreateExcluder(PrefsInterface* prefs) {
+  return std::make_unique<ExcluderStub>();
+}
+
+bool ExcluderStub::Exclude(const string& name) {
+  return true;
+}
+
+bool ExcluderStub::IsExcluded(const string& name) {
+  return false;
+}
+
+bool ExcluderStub::Reset() {
+  return true;
+}
+
+}  // namespace chromeos_update_engine
diff --git a/common/excluder_stub.h b/common/excluder_stub.h
new file mode 100644
index 0000000..2d5372a
--- /dev/null
+++ b/common/excluder_stub.h
@@ -0,0 +1,46 @@
+//
+// Copyright (C) 2020 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_COMMON_EXCLUDER_STUB_H_
+#define UPDATE_ENGINE_COMMON_EXCLUDER_STUB_H_
+
+#include <string>
+
+#include "update_engine/common/excluder_interface.h"
+
+namespace chromeos_update_engine {
+
+// An implementation of the |ExcluderInterface| that does nothing.
+class ExcluderStub : public ExcluderInterface {
+ public:
+  ExcluderStub() = default;
+  ~ExcluderStub() = default;
+
+  // |ExcluderInterface| overrides.
+  bool Exclude(const std::string& name) override;
+  bool IsExcluded(const std::string& name) override;
+  bool Reset() override;
+
+  // Not copyable or movable.
+  ExcluderStub(const ExcluderStub&) = delete;
+  ExcluderStub& operator=(const ExcluderStub&) = delete;
+  ExcluderStub(ExcluderStub&&) = delete;
+  ExcluderStub& operator=(ExcluderStub&&) = delete;
+};
+
+}  // namespace chromeos_update_engine
+
+#endif  // UPDATE_ENGINE_COMMON_EXCLUDER_STUB_H_
diff --git a/common/mock_excluder.h b/common/mock_excluder.h
new file mode 100644
index 0000000..bc54772
--- /dev/null
+++ b/common/mock_excluder.h
@@ -0,0 +1,37 @@
+//
+// Copyright (C) 2020 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef UPDATE_ENGINE_MOCK_APP_EXCLUDER_H_
+#define UPDATE_ENGINE_MOCK_APP_EXCLUDER_H_
+
+#include "update_engine/common/excluder_interface.h"
+
+#include <string>
+
+#include <gmock/gmock.h>
+
+namespace chromeos_update_engine {
+
+class MockExcluder : public ExcluderInterface {
+ public:
+  MOCK_METHOD(bool, Exclude, (const std::string&), (override));
+  MOCK_METHOD(bool, IsExcluded, (const std::string&), (override));
+  MOCK_METHOD(bool, Reset, (), (override));
+};
+
+}  // namespace chromeos_update_engine
+
+#endif  // UPDATE_ENGINE_MOCK_APP_EXCLUDER_H_