diff --git a/examples/index.ts b/examples/index.ts
index 3aba4b866..c660cbef8 100644
--- a/examples/index.ts
+++ b/examples/index.ts
@@ -6,6 +6,10 @@ import { Run } from './benchmark'
 
 // Todo: Investigate Union Default (initialize interior types)
 // Todo: Implement Value.Clean() Tests
-const T = Type.Tuple([Type.Number(), Type.Number()])
-const R = Value.Clean(T, [1, 2, 3])
+
+const X = Type.Object({ x: Type.Number() })
+const Y = Type.Object({ y: Type.Number() })
+const T = Type.Union([X, Y])
+const R = Value.Clean(T, { u: null, x: 1 })
+
 console.log(R)
diff --git a/test/runtime/value/clean/index.ts b/test/runtime/value/clean/index.ts
index 0343390fb..b290dd224 100644
--- a/test/runtime/value/clean/index.ts
+++ b/test/runtime/value/clean/index.ts
@@ -27,3 +27,8 @@ import './string'
 import './symbol'
 import './template-literal'
 import './tuple'
+import './uint8array'
+import './undefined'
+import './union'
+import './unknown'
+import './void'
diff --git a/test/runtime/value/clean/object.ts b/test/runtime/value/clean/object.ts
index bfe5bce32..805665a7e 100644
--- a/test/runtime/value/clean/object.ts
+++ b/test/runtime/value/clean/object.ts
@@ -3,6 +3,9 @@ import { Type } from '@sinclair/typebox'
 import { Assert } from '../../assert/index'
 
 describe('value/clean/Object', () => {
+  // ----------------------------------------------------------------
+  // Clean
+  // ----------------------------------------------------------------
   it('Should clean 1', () => {
     const T = Type.Object({ x: Type.Number() })
     const R = Value.Clean(T, null)
diff --git a/test/runtime/value/clean/uint8array.ts b/test/runtime/value/clean/uint8array.ts
new file mode 100644
index 000000000..732eb5b71
--- /dev/null
+++ b/test/runtime/value/clean/uint8array.ts
@@ -0,0 +1,11 @@
+import { Value } from '@sinclair/typebox/value'
+import { Type } from '@sinclair/typebox'
+import { Assert } from '../../assert/index'
+
+describe('value/clean/Uint8Array', () => {
+  it('Should clean 1', () => {
+    const T = Type.Uint8Array()
+    const R = Value.Clean(T, null)
+    Assert.IsEqual(R, null)
+  })
+})
diff --git a/test/runtime/value/clean/undefined.ts b/test/runtime/value/clean/undefined.ts
new file mode 100644
index 000000000..4b590c41b
--- /dev/null
+++ b/test/runtime/value/clean/undefined.ts
@@ -0,0 +1,11 @@
+import { Value } from '@sinclair/typebox/value'
+import { Type } from '@sinclair/typebox'
+import { Assert } from '../../assert/index'
+
+describe('value/clean/Undefined', () => {
+  it('Should clean 1', () => {
+    const T = Type.Undefined()
+    const R = Value.Clean(T, null)
+    Assert.IsEqual(R, null)
+  })
+})
diff --git a/test/runtime/value/clean/union.ts b/test/runtime/value/clean/union.ts
new file mode 100644
index 000000000..443e3d651
--- /dev/null
+++ b/test/runtime/value/clean/union.ts
@@ -0,0 +1,134 @@
+import { Value } from '@sinclair/typebox/value'
+import { Type } from '@sinclair/typebox'
+import { Assert } from '../../assert/index'
+
+describe('value/clean/Union', () => {
+  // ----------------------------------------------------------------
+  // Clean
+  // ----------------------------------------------------------------
+  it('Should clean 1', () => {
+    const T = Type.Union([Type.Number(), Type.Boolean()])
+    const R = Value.Clean(T, null)
+    Assert.IsEqual(R, null)
+  })
+  it('Should clean 2', () => {
+    const T = Type.Union([Type.Number(), Type.Boolean()])
+    const R = Value.Clean(T, 1)
+    Assert.IsEqual(R, 1)
+  })
+  it('Should clean 2', () => {
+    const T = Type.Union([Type.Number(), Type.Boolean()])
+    const R = Value.Clean(T, true)
+    Assert.IsEqual(R, true)
+  })
+  // ----------------------------------------------------------------
+  // Clean Select
+  // ----------------------------------------------------------------
+  it('Should clean select 1', () => {
+    const X = Type.Object({ x: Type.Number() })
+    const Y = Type.Object({ y: Type.Number() })
+    const T = Type.Union([X, Y])
+    const R = Value.Clean(T, null)
+    Assert.IsEqual(R, null)
+  })
+  it('Should clean select 2', () => {
+    const X = Type.Object({ x: Type.Number() })
+    const Y = Type.Object({ y: Type.Number() })
+    const T = Type.Union([X, Y])
+    const R = Value.Clean(T, {})
+    Assert.IsEqual(R, {})
+  })
+  it('Should clean select 3', () => {
+    const X = Type.Object({ x: Type.Number() })
+    const Y = Type.Object({ y: Type.Number() })
+    const T = Type.Union([X, Y])
+    const R = Value.Clean(T, { x: null })
+    Assert.IsEqual(R, { x: null })
+  })
+  it('Should clean select 4', () => {
+    const X = Type.Object({ x: Type.Number() })
+    const Y = Type.Object({ y: Type.Number() })
+    const T = Type.Union([X, Y])
+    const R = Value.Clean(T, { y: null })
+    Assert.IsEqual(R, { y: null })
+  })
+  // ----------------------------------------------------------------
+  // Clean Select Discard
+  // ----------------------------------------------------------------
+  it('Should clean select discard 1', () => {
+    const X = Type.Object({ x: Type.Number() })
+    const Y = Type.Object({ y: Type.Number() })
+    const T = Type.Union([X, Y])
+    const R = Value.Clean(T, null)
+    Assert.IsEqual(R, null)
+  })
+  it('Should clean select discard 2', () => {
+    const X = Type.Object({ x: Type.Number() })
+    const Y = Type.Object({ y: Type.Number() })
+    const T = Type.Union([X, Y])
+    const R = Value.Clean(T, { u: null })
+    Assert.IsEqual(R, { u: null }) // no match
+  })
+  it('Should clean select discard 3', () => {
+    const X = Type.Object({ x: Type.Number() })
+    const Y = Type.Object({ y: Type.Number() })
+    const T = Type.Union([X, Y])
+    const R = Value.Clean(T, { u: null, x: 1 })
+    Assert.IsEqual(R, { x: 1 })
+  })
+  it('Should clean select discard 4', () => {
+    const X = Type.Object({ x: Type.Number() })
+    const Y = Type.Object({ y: Type.Number() })
+    const T = Type.Union([X, Y])
+    const R = Value.Clean(T, { u: null, y: 1 })
+    Assert.IsEqual(R, { y: 1 })
+  })
+  // ----------------------------------------------------------------
+  // Clean Select Retain
+  // ----------------------------------------------------------------
+  it('Should clean select retain 1', () => {
+    const X = Type.Object({ x: Type.Number() }, { additionalProperties: Type.Null() })
+    const Y = Type.Object({ y: Type.Number() }, { additionalProperties: Type.Null() })
+    const T = Type.Union([X, Y])
+    const R = Value.Clean(T, null)
+    Assert.IsEqual(R, null)
+  })
+  it('Should clean select retain 2', () => {
+    const X = Type.Object({ x: Type.Number() }, { additionalProperties: Type.Null() })
+    const Y = Type.Object({ y: Type.Number() }, { additionalProperties: Type.Null() })
+    const T = Type.Union([X, Y])
+    const R = Value.Clean(T, { u: null })
+    Assert.IsEqual(R, { u: null })
+  })
+  it('Should clean select retain 3', () => {
+    const X = Type.Object({ x: Type.Number() }, { additionalProperties: Type.Null() })
+    const Y = Type.Object({ y: Type.Number() }, { additionalProperties: Type.Null() })
+    const T = Type.Union([X, Y])
+    const R = Value.Clean(T, { u: null, x: 1 })
+    Assert.IsEqual(R, { u: null, x: 1 })
+  })
+  it('Should clean select retain 4', () => {
+    const X = Type.Object({ x: Type.Number() }, { additionalProperties: Type.Null() })
+    const Y = Type.Object({ y: Type.Number() }, { additionalProperties: Type.Null() })
+    const T = Type.Union([X, Y])
+    const R = Value.Clean(T, { u: null, y: 1 })
+    Assert.IsEqual(R, { u: null, y: 1 })
+  })
+  // ----------------------------------------------------------------
+  // Clean Select First and Discard
+  // ----------------------------------------------------------------
+  it('Should clean select first and discard 1', () => {
+    const X = Type.Object({ x: Type.Number() })
+    const Y = Type.Object({ y: Type.Number() }, { additionalProperties: Type.Null() })
+    const T = Type.Union([X, Y])
+    const R = Value.Clean(T, { u: null, x: 1 })
+    Assert.IsEqual(R, { x: 1 })
+  })
+  it('Should clean select first and discard 2', () => {
+    const X = Type.Object({ x: Type.Number() })
+    const Y = Type.Object({ y: Type.Number() }, { additionalProperties: Type.Null() })
+    const T = Type.Union([X, Y])
+    const R = Value.Clean(T, { u: null, y: 1 })
+    Assert.IsEqual(R, { u: null, y: 1 })
+  })
+})
diff --git a/test/runtime/value/clean/unknown.ts b/test/runtime/value/clean/unknown.ts
new file mode 100644
index 000000000..edba3ebfc
--- /dev/null
+++ b/test/runtime/value/clean/unknown.ts
@@ -0,0 +1,11 @@
+import { Value } from '@sinclair/typebox/value'
+import { Type } from '@sinclair/typebox'
+import { Assert } from '../../assert/index'
+
+describe('value/clean/Unknown', () => {
+  it('Should clean 1', () => {
+    const T = Type.Unknown()
+    const R = Value.Clean(T, null)
+    Assert.IsEqual(R, null)
+  })
+})
diff --git a/test/runtime/value/clean/void.ts b/test/runtime/value/clean/void.ts
new file mode 100644
index 000000000..cd4c20db0
--- /dev/null
+++ b/test/runtime/value/clean/void.ts
@@ -0,0 +1,11 @@
+import { Value } from '@sinclair/typebox/value'
+import { Type } from '@sinclair/typebox'
+import { Assert } from '../../assert/index'
+
+describe('value/clean/Void', () => {
+  it('Should clean 1', () => {
+    const T = Type.Void()
+    const R = Value.Clean(T, null)
+    Assert.IsEqual(R, null)
+  })
+})