diff --git a/go/test/plan/v1/plan.pb.go b/go/test/plan/v1/plan.pb.go
index 68ae8cc..b5e39fb 100644
--- a/go/test/plan/v1/plan.pb.go
+++ b/go/test/plan/v1/plan.pb.go
@@ -70,6 +70,60 @@
 	return fileDescriptor_1a74b4d4119f628f, []int{5, 0}
 }
 
+type Exclusion_Action int32
+
+const (
+	// Specify no action.
+	//
+	// The Test Lab Environment may choose any of the available actions based
+	// on internal heuristics.
+	//
+	// The default Action is a good default if none of the considersations for
+	// the specific actions below apply.
+	Exclusion_ACTION_UNSPECIFIED Exclusion_Action = 0
+	// Do not schedule the selected Tests on specified Devices Under Test.
+	//
+	// It is especially useful to set this Action for permanent exceptions as it
+	// is definitely not useful to run the Tests at all in those cases.
+	Exclusion_DO_NOT_SCHEDULE Exclusion_Action = 1
+	// Schedule the Test on Devices Under Test as required by the test plan
+	// unit, but mark the results for selected tests on the specified Devices
+	// Under Test as non-critical. Results marked non-critical are intended to
+	// be ignored by result consumers (e.g, presubmit system should consider the
+	// result irrelevant for validatting a Chrome OS build).
+	//
+	// This action does not guarantee that results for the selected (Test,
+	// Device Under Test) pairs are always available because that depends no how
+	// the test plan Unit is interpreted overall. When this action is set, the
+	// Test Lab Environment SHOULD NOT make any special effort to include /
+	// exclude the selected (Test, Device Under Test) pairs.
+	//
+	// It is useful to set this Action for temporary exclusions where the
+	// results generated from test execution can be uesd to root cause and fix
+	// the underlying issues.
+	Exclusion_MARK_NON_CRITICAL Exclusion_Action = 2
+)
+
+var Exclusion_Action_name = map[int32]string{
+	0: "ACTION_UNSPECIFIED",
+	1: "DO_NOT_SCHEDULE",
+	2: "MARK_NON_CRITICAL",
+}
+
+var Exclusion_Action_value = map[string]int32{
+	"ACTION_UNSPECIFIED": 0,
+	"DO_NOT_SCHEDULE":    1,
+	"MARK_NON_CRITICAL":  2,
+}
+
+func (x Exclusion_Action) String() string {
+	return proto.EnumName(Exclusion_Action_name, int32(x))
+}
+
+func (Exclusion_Action) EnumDescriptor() ([]byte, []int) {
+	return fileDescriptor_1a74b4d4119f628f, []int{5, 1}
+}
+
 // A set of known test plans.
 //
 // In practice, a complete specification of all known plans may consist of
@@ -627,7 +681,8 @@
 // temporary or permanent reasons.
 type Exclusion struct {
 	// Required.
-	Type Exclusion_Type `protobuf:"varint,1,opt,name=type,proto3,enum=test.plan.v1.Exclusion_Type" json:"type,omitempty"`
+	Type   Exclusion_Type   `protobuf:"varint,1,opt,name=type,proto3,enum=test.plan.v1.Exclusion_Type" json:"type,omitempty"`
+	Action Exclusion_Action `protobuf:"varint,5,opt,name=action,proto3,enum=test.plan.v1.Exclusion_Action" json:"action,omitempty"`
 	// The tests this exclusion applies to, within a test plan unit.
 	//
 	// Tests selected by this condition that are not in the test plan unit are
@@ -687,6 +742,13 @@
 	return Exclusion_TYPE_UNSPECIFIED
 }
 
+func (m *Exclusion) GetAction() Exclusion_Action {
+	if m != nil {
+		return m.Action
+	}
+	return Exclusion_ACTION_UNSPECIFIED
+}
+
 func (m *Exclusion) GetTestConstraint() *TestConstraint {
 	if m != nil {
 		return m.TestConstraint
@@ -992,6 +1054,7 @@
 
 func init() {
 	proto.RegisterEnum("test.plan.v1.Exclusion_Type", Exclusion_Type_name, Exclusion_Type_value)
+	proto.RegisterEnum("test.plan.v1.Exclusion_Action", Exclusion_Action_name, Exclusion_Action_value)
 	proto.RegisterType((*Specification)(nil), "test.plan.v1.Specification")
 	proto.RegisterType((*Plan)(nil), "test.plan.v1.Plan")
 	proto.RegisterType((*Unit)(nil), "test.plan.v1.Unit")
@@ -1009,48 +1072,53 @@
 func init() { proto.RegisterFile("test/plan/v1/plan.proto", fileDescriptor_1a74b4d4119f628f) }
 
 var fileDescriptor_1a74b4d4119f628f = []byte{
-	// 680 bytes of a gzipped FileDescriptorProto
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-	0xc2, 0x50, 0x5b, 0x65, 0xf4, 0x05, 0x00, 0x00,
+	// 755 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xac, 0x55, 0xdd, 0x8e, 0xe3, 0x34,
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+	0x6b, 0x38, 0x6e, 0xde, 0x05, 0x0f, 0x36, 0xf3, 0x25, 0x68, 0xcf, 0x53, 0xb2, 0xa4, 0x69, 0x52,
+	0x72, 0xf4, 0x99, 0x38, 0xa2, 0x9c, 0x85, 0x39, 0xe1, 0x8b, 0xfa, 0x86, 0xd6, 0xb0, 0x26, 0x90,
+	0xb1, 0x00, 0x9e, 0xff, 0xf0, 0xfa, 0x72, 0xce, 0x36, 0xad, 0x59, 0xac, 0x98, 0xdb, 0x8d, 0x47,
+	0x20, 0xc9, 0x66, 0x05, 0xb1, 0xe5, 0xb5, 0x6f, 0xcf, 0x99, 0xdd, 0x7c, 0x5e, 0x2e, 0xc5, 0xf7,
+	0xed, 0xa1, 0x9c, 0xfb, 0xfa, 0xdf, 0x00, 0x00, 0x00, 0xff, 0xff, 0x67, 0xa0, 0x6d, 0xe0, 0x7a,
+	0x06, 0x00, 0x00,
 }
diff --git a/src/test/plan/v1/plan.proto b/src/test/plan/v1/plan.proto
index 710de88..4a77ab8 100644
--- a/src/test/plan/v1/plan.proto
+++ b/src/test/plan/v1/plan.proto
@@ -309,6 +309,41 @@
   // Required.
   Type type = 1;
 
+  enum Action {
+    // Specify no action.
+    //
+    // The Test Lab Environment may choose any of the available actions based
+    // on internal heuristics.
+    //
+    // The default Action is a good default if none of the considersations for
+    // the specific actions below apply.
+    ACTION_UNSPECIFIED = 0;
+
+    // Do not schedule the selected Tests on specified Devices Under Test.
+    //
+    // It is especially useful to set this Action for permanent exceptions as it
+    // is definitely not useful to run the Tests at all in those cases.
+    DO_NOT_SCHEDULE = 1;
+
+    // Schedule the Test on Devices Under Test as required by the test plan
+    // unit, but mark the results for selected tests on the specified Devices
+    // Under Test as non-critical. Results marked non-critical are intended to
+    // be ignored by result consumers (e.g, presubmit system should consider the
+    // result irrelevant for validatting a Chrome OS build).
+    //
+    // This action does not guarantee that results for the selected (Test,
+    // Device Under Test) pairs are always available because that depends no how
+    // the test plan Unit is interpreted overall. When this action is set, the
+    // Test Lab Environment SHOULD NOT make any special effort to include /
+    // exclude the selected (Test, Device Under Test) pairs.
+    //
+    // It is useful to set this Action for temporary exclusions where the
+    // results generated from test execution can be uesd to root cause and fix
+    // the underlying issues.
+    MARK_NON_CRITICAL = 2;
+  }
+  Action action = 5;
+
   // The tests this exclusion applies to, within a test plan unit.
   //
   // Tests selected by this condition that are not in the test plan unit are