diff --git a/protect/control/v1/common.proto b/protect/control/v1/common.proto
index 0a24486..8b9d33a 100644
--- a/protect/control/v1/common.proto
+++ b/protect/control/v1/common.proto
@@ -26,6 +26,9 @@ message ZoneSpec {
   ZoneVirtualizationOptionsSpec virtualization_options = 9;
   ZoneScratchDiskSpec scratch_disk = 10;
   repeated OciImageSpec addons = 11;
+  // When set, this zone is a fork of the named parent zone; the reconciler
+  // forks the child from the parent rather than building it from scratch.
+  string fork_parent_zone_id = 12;
 }
 
 enum ZoneResourceAdjustmentPolicy {
@@ -215,6 +218,7 @@ enum ZoneState {
   ZONE_STATE_SUSPENDING = 8;
   ZONE_STATE_SUSPENDED = 9;
   ZONE_STATE_RESUMING = 10;
+  ZONE_STATE_FORKING = 11;
 }
 
 enum ZoneNetworkIpVersion {
diff --git a/protect/control/v1/control.proto b/protect/control/v1/control.proto
index c9796a0..df48240 100644
--- a/protect/control/v1/control.proto
+++ b/protect/control/v1/control.proto
@@ -24,6 +24,7 @@ service ControlService {
   rpc DestroyZone(DestroyZoneRequest) returns (DestroyZoneReply);
   rpc SuspendZone(SuspendZoneRequest) returns (SuspendZoneReply);
   rpc ResumeZone(ResumeZoneRequest) returns (ResumeZoneReply);
+  rpc ForkZone(ForkZoneRequest) returns (ForkZoneReply);
 
   rpc ResolveZoneId(ResolveZoneIdRequest) returns (ResolveZoneIdReply);
   rpc ResolveZoneIds(ResolveZoneIdsRequest) returns (ResolveZoneIdsReply);
@@ -113,6 +114,21 @@ message ResumeZoneRequest {
 
 message ResumeZoneReply {}
 
+// Forks a running Edera zone into a new memory-shared child zone (Xen VM-fork).
+// The parent is cooperatively suspended for the fork and then resumed; the child
+// is a copy-on-write clone that boots with its own identity (UUID, network).
+message ForkZoneRequest {
+  // The zone to fork from.
+  string zone_id = 1;
+  // Optional name for the forked child zone.
+  string name = 2;
+}
+
+// Returns the UUID of the newly forked child zone.
+message ForkZoneReply {
+  string zone_id = 1;
+}
+
 // Resolves zone "friendly name" to a singular zone UUID, if possible. Matching is exact.
 // See also `ResolveZoneIdsRequest` (plural).
 message ResolveZoneIdRequest {