diff --git a/projects/clr/rocclr/device/devhostcall.cpp b/projects/clr/rocclr/device/devhostcall.cpp
index a73c4451b9..c49ecc0126 100644
--- a/projects/clr/rocclr/device/devhostcall.cpp
+++ b/projects/clr/rocclr/device/devhostcall.cpp
@@ -335,10 +335,10 @@ void HostcallListener::removeBuffer(HostcallBuffer* buffer) {
 
 bool HostcallListener::initialize(const amd::Device &dev) {
   doorbell_ = dev.createSignal();
-#ifdef WITH_HSA_DEVICE
-  auto ws = device::Signal::WaitState::Blocked;
-#else
+#if defined(WITH_PAL_DEVICE) && !defined(_WIN32)
   auto ws = device::Signal::WaitState::Active;
+#else
+  auto ws = device::Signal::WaitState::Blocked;
 #endif
   if ((doorbell_ == nullptr) || !doorbell_->Init(dev, SIGNAL_INIT, ws)) {
     return false;
diff --git a/projects/clr/rocclr/device/pal/palsignal.cpp b/projects/clr/rocclr/device/pal/palsignal.cpp
index 4f7ac33ccf..0764647419 100644
--- a/projects/clr/rocclr/device/pal/palsignal.cpp
+++ b/projects/clr/rocclr/device/pal/palsignal.cpp
@@ -29,6 +29,21 @@ namespace pal {
 
 Signal::~Signal() {
   dev_->context().svmFree(amdSignal_);
+
+  if (ws_ == device::Signal::WaitState::Blocked) {
+#if defined(_WIN32)
+    Pal::Result result = Pal::Result::Success;
+
+    Pal::UnregisterEventInfo eventInfo = {};
+    eventInfo.pEvent = &event_;
+    eventInfo.trackingType = Pal::EventTrackingType::ShaderInterrupt;
+    result = dev_->iDev()->UnregisterEvent(eventInfo);
+    if (result != Pal::Result::Success) {
+      ClPrint(amd::LOG_ERROR, amd::LOG_QUEUE,
+              "Failed to unregister SQ event needed for hostcall buffer");
+    }
+#endif
+  }
 }
 
 bool Signal::Init(const amd::Device& dev, uint64_t init, device::Signal::WaitState ws) {
@@ -47,6 +62,47 @@ bool Signal::Init(const amd::Device& dev, uint64_t init, device::Signal::WaitSta
   amdSignal_ = new (buffer) amd_signal_t();
   amdSignal_->value = init;
 
+  if (ws_ == device::Signal::WaitState::Blocked) {
+#if defined(_WIN32)
+    Pal::Result result = Pal::Result::Success;
+
+    Util::EventCreateFlags flags = {};
+    flags.manualReset = false;
+    flags.initiallySignaled = false;
+    result = event_.Init(flags);
+    if (result != Pal::Result::Success) {
+      ClPrint(amd::LOG_ERROR, amd::LOG_QUEUE,
+              "Failed to create Pal::Util::Event needed for hostcall buffer");
+      return false;
+    }
+
+    result = event_.Set();
+    if (result != Pal::Result::Success) {
+      ClPrint(amd::LOG_ERROR, amd::LOG_QUEUE,
+              "Failed to set Pal::Util::Event needed for hostcall buffer");
+      return false;
+    }
+
+    Pal::RegisterEventInfo eventInputInfo = {};
+    eventInputInfo.pEvent = &event_;
+    eventInputInfo.trackingType = Pal::EventTrackingType::ShaderInterrupt;
+    Pal::RegisterEventOutputInfo eventOutputInfo = {};
+    result = dev_->iDev()->RegisterEvent(
+      eventInputInfo,
+      &eventOutputInfo);
+    if (result != Pal::Result::Success) {
+      ClPrint(amd::LOG_ERROR, amd::LOG_QUEUE,
+              "Failed to register SQ event needed for hostcall buffer");
+      return false;
+    }
+    amdSignal_->event_id = eventOutputInfo.shaderInterrupt.eventId;
+    amdSignal_->event_mailbox_ptr = eventOutputInfo.shaderInterrupt.eventMailboxGpuVa;
+    ClPrint(amd::LOG_INFO, amd::LOG_INIT,
+            "Registered SQ event %d with mailbox slot %p",
+            amdSignal_->event_id, amdSignal_->event_mailbox_ptr);
+#endif
+  }
+
   return true;
 }
 
@@ -67,7 +123,19 @@ uint64_t Signal::Wait(uint64_t value, device::Signal::Condition c, uint64_t time
   } (c);
 
   if (ws_ == device::Signal::WaitState::Blocked) {
-    guarantee(false, "Unimplemented");
+#if defined(_WIN32)
+    Pal::Result result = Pal::Result::Success;
+
+    float timeoutInSec = timeout / (1000 * 1000);
+    result = event_.Wait(timeoutInSec);
+
+    if (result != Pal::Result::Success) {
+      return -1;
+    }
+
+    std::atomic_thread_fence(std::memory_order_acquire);
+    return amdSignal_->value;
+#endif
   } else if (ws_ == device::Signal::WaitState::Active) {
     auto start = amd::Os::timeNanos();
     while (true) {
diff --git a/projects/clr/rocclr/device/pal/palsignal.hpp b/projects/clr/rocclr/device/pal/palsignal.hpp
index d043c6a921..781cbd6b1f 100644
--- a/projects/clr/rocclr/device/pal/palsignal.hpp
+++ b/projects/clr/rocclr/device/pal/palsignal.hpp
@@ -24,6 +24,8 @@
 
 #include <amd_hsa_signal.h>
 
+#include "palEvent.h"
+
 namespace pal {
 
 class Device;
@@ -32,6 +34,7 @@ class Signal: public device::Signal {
 private:
   const Device* dev_;
   amd_signal_t* amdSignal_;
+  Util::Event   event_;
 
 public:
   ~Signal() override;