diff --git a/examples/messaging_recvonly_sample/src/messaging_recvonly_sample.cpp b/examples/messaging_recvonly_sample/src/messaging_recvonly_sample.cpp
index e6d88f4c..b5d85512 100644
--- a/examples/messaging_recvonly_sample/src/messaging_recvonly_sample.cpp
+++ b/examples/messaging_recvonly_sample/src/messaging_recvonly_sample.cpp
@@ -1,6 +1,3 @@
-// WebRTC
-#include <api/environment/environment_factory.h>
-
 // Sora
 #include <sora/sora_client_context.h>
 
@@ -197,8 +194,7 @@ int main(int argc, char* argv[]) {
   sora::SoraClientContextConfig context_config;
   context_config.use_audio_device = false;
   context_config.use_hardware_encoder = false;
-  auto env = webrtc::CreateEnvironment();
-  auto context = sora::SoraClientContext::Create(context_config, env);
+  auto context = sora::SoraClientContext::Create(context_config);
 
   auto messaging_recvonly_sample =
       std::make_shared<MessagingRecvOnlySample>(context, config);
diff --git a/examples/sdl_sample/src/sdl_sample.cpp b/examples/sdl_sample/src/sdl_sample.cpp
index e7875a7b..20a404c9 100644
--- a/examples/sdl_sample/src/sdl_sample.cpp
+++ b/examples/sdl_sample/src/sdl_sample.cpp
@@ -1,6 +1,3 @@
-// WebRTC
-#include <api/environment/environment_factory.h>
-
 // Sora
 #include <sora/camera_device_capturer.h>
 #include <sora/sora_client_context.h>
@@ -251,9 +248,8 @@ int main(int argc, char* argv[]) {
     rtc::LogMessage::LogThreads();
   }
 
-  auto env = webrtc::CreateEnvironment();
   auto context =
-      sora::SoraClientContext::Create(sora::SoraClientContextConfig(), env);
+      sora::SoraClientContext::Create(sora::SoraClientContextConfig());
   auto sdlsample = std::make_shared<SDLSample>(context, config);
   sdlsample->Run();
 
diff --git a/examples/sumomo/src/sumomo.cpp b/examples/sumomo/src/sumomo.cpp
index 516d055e..702dbacc 100644
--- a/examples/sumomo/src/sumomo.cpp
+++ b/examples/sumomo/src/sumomo.cpp
@@ -1,6 +1,3 @@
-// WebRTC
-#include <api/environment/environment_factory.h>
-
 // Sora
 #include <sora/camera_device_capturer.h>
 #include <sora/sora_client_context.h>
@@ -450,8 +447,7 @@ int main(int argc, char* argv[]) {
     context_config.use_hardware_encoder = *use_hardware_encoder;
   }
   context_config.openh264 = openh264;
-  auto env = webrtc::CreateEnvironment();
-  auto context = sora::SoraClientContext::Create(context_config, env);
+  auto context = sora::SoraClientContext::Create(context_config);
   auto sumomo = std::make_shared<Sumomo>(context, config);
   sumomo->Run();
 
diff --git a/include/sora/sora_client_context.h b/include/sora/sora_client_context.h
index 18987dad..26e31ae8 100644
--- a/include/sora/sora_client_context.h
+++ b/include/sora/sora_client_context.h
@@ -2,6 +2,7 @@
 #define SORA_SORA_CLIENT_CONTEXT_H_
 
 // WebRTC
+#include <api/environment/environment_factory.h>
 #include <api/peer_connection_interface.h>
 #include <media/engine/webrtc_media_engine.h>
 #include <pc/connection_context.h>
@@ -59,6 +60,13 @@ class SoraClientContext {
       const SoraClientContextConfig& config,
       webrtc::Environment& env);
 
+  static std::shared_ptr<SoraClientContext> Create(
+      const SoraClientContextConfig& config) {
+    // TODO(enm10k): ライフタイム的には env をクラスで保持した方が良さそうだが、 Create が static なメソッドなので難しい気がする
+    auto env = webrtc::CreateEnvironment();
+    return Create(SoraClientContextConfig(), env);
+  };
+
   ~SoraClientContext();
 
   rtc::Thread* network_thread() const { return network_thread_.get(); }
diff --git a/src/sora_client_context.cpp b/src/sora_client_context.cpp
index dd9cc778..446b8134 100644
--- a/src/sora_client_context.cpp
+++ b/src/sora_client_context.cpp
@@ -5,7 +5,6 @@
 #include <api/audio_codecs/builtin_audio_encoder_factory.h>
 #include <api/create_peerconnection_factory.h>
 #include <api/enable_media.h>
-// #include <api/environment/environment_factory.h>
 #include <api/rtc_event_log/rtc_event_log_factory.h>
 #include <api/task_queue/default_task_queue_factory.h>
 #include <call/call_config.h>