diff --git a/src/application.cpp b/src/application.cpp
index b72335a..995262e 100644
--- a/src/application.cpp
+++ b/src/application.cpp
@@ -33,12 +33,12 @@ static std::mutex app_mutex;
 Application::Logger::Logger(std::string name) {
   auto app = Application::GetInstance();
 
-  if (app->HasMonitor(name)) {
-    cur_monitor_ = app->GetMonitor(name);
-    cur_monitor_->Enter();
-  } else {
-    throw NotFoundError("Logger", "Monitor " + name);
+  if (!app->HasMonitor(name)) {
+    app->InstallMonitor(name, "stdout", "stderr");
   }
+
+  cur_monitor_ = app->GetMonitor(name);
+  cur_monitor_->Enter();
 }
 
 Application::Logger::~Logger() { cur_monitor_->Leave(); }
diff --git a/src/monitor.cpp b/src/monitor.cpp
index 20a3103..2641414 100644
--- a/src/monitor.cpp
+++ b/src/monitor.cpp
@@ -9,6 +9,10 @@
 #include "application.hpp"
 #include "monitor.hpp"
 
+struct NullDeleter {
+  void operator()(void const*) const {}
+};
+
 static std::mutex section_mutex;
 
 void Monitor::Log(std::string const& msg) {
@@ -47,6 +51,9 @@ void Monitor::Enter() {
 void Monitor::Leave() {
   std::unique_lock<std::mutex> lock(section_mutex);
 
+  log_device_->flush();
+  err_device_->flush();
+
   sections_.pop_back();
   if (sections_.size() > 0) sections_.back() += 1;
 }
@@ -57,7 +64,11 @@ bool Monitor::SetLogOutput(std::string const& fname) {
   if (app->HasDevice(fname)) {
     log_device_ = app->GetDevice(fname);
   } else {
-    log_device_ = std::make_shared<std::ofstream>(fname, std::ios::out);
+    if (fname == "stdout") {
+      log_device_ = std::shared_ptr<std::ostream>(&std::cout, NullDeleter());
+    } else {
+      log_device_ = std::make_shared<std::ofstream>(fname, std::ios::out);
+    }
     app->InstallDevice(fname, log_device_);
   }
 
@@ -70,7 +81,11 @@ bool Monitor::SetErrOutput(std::string const& fname) {
   if (app->HasDevice(fname)) {
     err_device_ = app->GetDevice(fname);
   } else {
-    err_device_ = std::make_shared<std::ofstream>(fname, std::ios::out);
+    if (fname == "stderr") {
+      err_device_ = std::shared_ptr<std::ostream>(&std::cerr, NullDeleter());
+    } else {
+      err_device_ = std::make_shared<std::ofstream>(fname, std::ios::out);
+    }
     app->InstallDevice(fname, err_device_);
   }
 
@@ -97,6 +112,13 @@ std::string Monitor::getSectionID() const {
   }
 }
 
+void Monitor::Start() {
+  std::unique_lock<std::mutex> lock(section_mutex);
+
+  sections_.clear();
+  sections_.push_back(1);
+}
+
 void Monitor::advance() {
   std::unique_lock<std::mutex> lock(section_mutex);
 
diff --git a/src/monitor.hpp b/src/monitor.hpp
index fe642cf..73ad712 100644
--- a/src/monitor.hpp
+++ b/src/monitor.hpp
@@ -63,7 +63,7 @@ class Monitor {
 
   bool SetErrOutput(std::string const& fname);
 
-  static void Start() { advance(); }
+  static void Start();
 
  protected:
   virtual std::string getTimeStamp() const;
diff --git a/tests/03_output_to_screen.cpp b/tests/03_output_to_screen.cpp
new file mode 100644
index 0000000..e790409
--- /dev/null
+++ b/tests/03_output_to_screen.cpp
@@ -0,0 +1,27 @@
+// C/C++
+#include <iostream>
+
+// application
+#include <application/application.hpp>
+
+void func2() {
+  Application::Logger app("B");
+
+  app->Log("First step");
+  app->Log("Second step");
+}
+
+void func1() {
+  Application::Logger app("A");
+
+  app->Log("First step");
+  app->Log("Second step");
+
+  func2();
+}
+
+int main(int argc, char **argv) {
+  func1();
+
+  Application::Destroy();
+}