diff --git a/openfeature/client_api.h b/openfeature/client_api.h
index ceecaaa..b3c7e34 100644
--- a/openfeature/client_api.h
+++ b/openfeature/client_api.h
@@ -113,11 +113,17 @@ template <typename ResolutionDetailsType, typename ValueType,
 std::unique_ptr<ResolutionDetailsType> ClientAPI::EvaluateFlag(
     ValueType default_value, const std::optional<EvaluationContext>& ctx,
     ProviderCallable provider_call) {
-  if (GetProviderStatus() != ProviderStatus::kReady) {
+  ProviderStatus status = GetProviderStatus();
+  if (status == ProviderStatus::kNotReady) {
     return std::make_unique<ResolutionDetailsType>(
         default_value, Reason::kError, std::nullopt, FlagMetadata(),
         ErrorCode::kProviderNotReady, "Provider is not ready");
   }
+  if (status == ProviderStatus::kFatal) {
+    return std::make_unique<ResolutionDetailsType>(
+        default_value, Reason::kError, std::nullopt, FlagMetadata(),
+        ErrorCode::kProviderFatal, "Provider is in fatal error state");
+  }
 
   std::shared_ptr<FeatureProvider> provider =
       provider_repository_.GetProvider(domain_);
diff --git a/test/client_api_test.cpp b/test/client_api_test.cpp
index f718e39..19f36f9 100644
--- a/test/client_api_test.cpp
+++ b/test/client_api_test.cpp
@@ -14,6 +14,7 @@
 
 using ::openfeature::BoolResolutionDetails;
 using ::openfeature::ClientAPI;
+using ::openfeature::ErrorCode;
 using ::openfeature::EvaluationContext;
 using ::openfeature::FlagMetadata;
 using ::openfeature::GlobalContextManager;
@@ -318,4 +319,65 @@ TEST_F(ClientAPITest, EvaluateFlagHandlesProviderUnknownException) {
 
   EXPECT_FALSE(client.GetBooleanValue("flag", false));
   EXPECT_TRUE(client.GetBooleanValue("flag", true));
-}
\ No newline at end of file
+}
+
+TEST_F(ClientAPITest, EvaluateFlagBlocksWhenProviderNotReady) {
+  auto mock_provider = std::make_shared<NiceMock<MockFeatureProvider>>();
+  EXPECT_CALL(*mock_provider, GetBooleanEvaluation(_, _, _)).Times(0);
+  repo_.SetProvider("test-domain", mock_provider,
+                    EvaluationContext::Builder().build(), true);
+
+  auto status_manager = repo_.GetFeatureProviderStatusManager("test-domain");
+  ASSERT_NE(status_manager, nullptr);
+  status_manager->SetStatus(ProviderStatus::kNotReady);
+  ClientAPI client(repo_, "test-domain");
+
+  EXPECT_TRUE(client.GetBooleanValue("flag", true));
+  EXPECT_FALSE(client.GetBooleanValue("flag", false));
+}
+
+TEST_F(ClientAPITest, EvaluateFlagBlocksWhenProviderFatal) {
+  auto mock_provider = std::make_shared<NiceMock<MockFeatureProvider>>();
+  EXPECT_CALL(*mock_provider, GetBooleanEvaluation(_, _, _)).Times(0);
+  repo_.SetProvider("test-domain", mock_provider,
+                    EvaluationContext::Builder().build(), true);
+
+  auto status_manager = repo_.GetFeatureProviderStatusManager("test-domain");
+  ASSERT_NE(status_manager, nullptr);
+  status_manager->SetStatus(ProviderStatus::kFatal);
+  ClientAPI client(repo_, "test-domain");
+
+  EXPECT_TRUE(client.GetBooleanValue("flag", true));
+}
+
+TEST_F(ClientAPITest, EvaluateFlagProceedsWhenProviderInErrorState) {
+  auto mock_provider = std::make_shared<NiceMock<MockFeatureProvider>>();
+  EXPECT_CALL(*mock_provider, GetBooleanEvaluation("flag", false, _))
+      .WillOnce(Return(std::make_unique<BoolResolutionDetails>(
+          true, Reason::kCached, std::nullopt, FlagMetadata())));
+  repo_.SetProvider("test-domain", mock_provider,
+                    EvaluationContext::Builder().build(), true);
+
+  auto status_manager = repo_.GetFeatureProviderStatusManager("test-domain");
+  ASSERT_NE(status_manager, nullptr);
+  status_manager->SetStatus(ProviderStatus::kError);
+  ClientAPI client(repo_, "test-domain");
+
+  EXPECT_TRUE(client.GetBooleanValue("flag", false));
+}
+
+TEST_F(ClientAPITest, EvaluateFlagProceedsWhenProviderInStaleState) {
+  auto mock_provider = std::make_shared<NiceMock<MockFeatureProvider>>();
+  EXPECT_CALL(*mock_provider, GetBooleanEvaluation("flag", false, _))
+      .WillOnce(Return(std::make_unique<BoolResolutionDetails>(
+          true, Reason::kCached, std::nullopt, FlagMetadata())));
+  repo_.SetProvider("test-domain", mock_provider,
+                    EvaluationContext::Builder().build(), true);
+
+  auto status_manager = repo_.GetFeatureProviderStatusManager("test-domain");
+  ASSERT_NE(status_manager, nullptr);
+  status_manager->SetStatus(ProviderStatus::kStale);
+  ClientAPI client(repo_, "test-domain");
+
+  EXPECT_TRUE(client.GetBooleanValue("flag", false));
+}