diff --git a/zion/include/zcall.h b/zion/include/zcall.h
index 1ea7558..a610454 100644
--- a/zion/include/zcall.h
+++ b/zion/include/zcall.h
@@ -30,6 +30,7 @@ SYS3(MemoryObjectCreateContiguous, uint64_t, size, z_cap_t*, vmmo_cap,
 
 SYS4(MemoryObjectDuplicate, z_cap_t, vmmo_cap, uint64_t, base_offset, uint64_t,
      length, z_cap_t*, new_vmmo_cap);
+SYS2(MemoryObjectInspect, z_cap_t, vmmo_cap, uint64_t*, size);
 
 SYS2(ChannelCreate, z_cap_t*, channel1, z_cap_t*, channel2);
 SYS5(ChannelSend, z_cap_t, chan_cap, uint64_t, num_bytes, const void*, data,
diff --git a/zion/include/ztypes.h b/zion/include/ztypes.h
index a57cb6a..ebbb4c7 100644
--- a/zion/include/ztypes.h
+++ b/zion/include/ztypes.h
@@ -28,6 +28,7 @@ const uint64_t kZionMemoryObjectCreatePhysical = 0x31;
 const uint64_t kZionMemoryObjectCreateContiguous = 0x32;
 
 const uint64_t kZionMemoryObjectDuplicate = 0x38;
+const uint64_t kZionMemoryObjectInspect = 0x39;
 
 // IPC Calls
 const uint64_t kZionChannelCreate = 0x40;
diff --git a/zion/syscall/memory_object.cpp b/zion/syscall/memory_object.cpp
index ae268c4..5457cb6 100644
--- a/zion/syscall/memory_object.cpp
+++ b/zion/syscall/memory_object.cpp
@@ -33,7 +33,6 @@ z_err_t MemoryObjectCreateContiguous(ZMemoryObjectCreateContiguousReq* req) {
 z_err_t MemoryObjectDuplicate(ZMemoryObjectDuplicateReq* req) {
   auto& curr_proc = gScheduler->CurrentProcess();
   auto vmmo_cap = curr_proc.GetCapability(req->vmmo_cap);
-  // FIXME: Check a duplication permission here.
   RET_ERR(ValidateCapability<MemoryObject>(vmmo_cap, kZionPerm_Duplicate));
 
   ASSIGN_OR_RETURN(
@@ -43,3 +42,14 @@ z_err_t MemoryObjectDuplicate(ZMemoryObjectDuplicateReq* req) {
       curr_proc.AddNewCapability(new_vmmo, vmmo_cap->permissions());
   return glcr::OK;
 }
+
+z_err_t MemoryObjectInspect(ZMemoryObjectInspectReq* req) {
+  auto& curr_proc = gScheduler->CurrentProcess();
+  auto vmmo_cap = curr_proc.GetCapability(req->vmmo_cap);
+  RET_ERR(ValidateCapability<MemoryObject>(vmmo_cap, kZionPerm_Read));
+
+  auto vmmo = vmmo_cap->obj<MemoryObject>();
+  *req->size = vmmo->size();
+
+  return glcr::OK;
+}
diff --git a/zion/syscall/memory_object.h b/zion/syscall/memory_object.h
index 155be97..5805345 100644
--- a/zion/syscall/memory_object.h
+++ b/zion/syscall/memory_object.h
@@ -6,3 +6,4 @@ z_err_t MemoryObjectCreate(ZMemoryObjectCreateReq* req);
 z_err_t MemoryObjectCreatePhysical(ZMemoryObjectCreatePhysicalReq* req);
 z_err_t MemoryObjectCreateContiguous(ZMemoryObjectCreateContiguousReq* req);
 z_err_t MemoryObjectDuplicate(ZMemoryObjectDuplicateReq* req);
+z_err_t MemoryObjectInspect(ZMemoryObjectInspectReq* req);
diff --git a/zion/syscall/syscall.cpp b/zion/syscall/syscall.cpp
index d21392c..89ee5b8 100644
--- a/zion/syscall/syscall.cpp
+++ b/zion/syscall/syscall.cpp
@@ -66,6 +66,7 @@ extern "C" z_err_t SyscallHandler(uint64_t call_id, void* req) {
     CASE(MemoryObjectCreatePhysical);
     CASE(MemoryObjectCreateContiguous);
     CASE(MemoryObjectDuplicate);
+    CASE(MemoryObjectInspect);
     // syscall/ipc.h
     CASE(ChannelCreate);
     CASE(ChannelSend);