diff --git a/include/crow/app.h b/include/crow/app.h
index d9c87ab74..ec1b27e93 100644
--- a/include/crow/app.h
+++ b/include/crow/app.h
@@ -156,8 +156,8 @@ namespace crow
         /// Run the server on multiple threads using a specific number
         self_t& concurrency(std::uint16_t concurrency)
         {
-            if (concurrency < 1)
-                concurrency = 1;
+            if (concurrency < 2) // Crow can have a minimum of 2 threads running
+                concurrency = 2;
             concurrency_ = concurrency;
             return *this;
         }
@@ -420,7 +420,7 @@ namespace crow
     private:
         std::uint8_t timeout_{5};
         uint16_t port_ = 80;
-        uint16_t concurrency_ = 1;
+        uint16_t concurrency_ = 2;
         bool validated_ = false;
         std::string server_name_ = std::string("Crow/") + VERSION;
         std::string bindaddr_ = "0.0.0.0";
diff --git a/include/crow/http_server.h b/include/crow/http_server.h
index e3b747e83..9cbedf0b5 100644
--- a/include/crow/http_server.h
+++ b/include/crow/http_server.h
@@ -31,12 +31,12 @@ namespace crow
           signals_(io_service_),
           tick_timer_(io_service_),
           handler_(handler),
-          concurrency_(concurrency == 0 ? 1 : concurrency),
+          concurrency_(concurrency),
           timeout_(timeout),
           server_name_(server_name),
           port_(port),
           bindaddr_(bindaddr),
-          task_queue_length_pool_(concurrency_),
+          task_queue_length_pool_(concurrency_ - 1),
           middlewares_(middlewares),
           adaptor_ctx_(adaptor_ctx)
         {}
@@ -60,14 +60,15 @@ namespace crow
 
         void run()
         {
-            for (int i = 0; i < concurrency_; i++)
+            uint16_t worker_thread_count = concurrency_ - 1;
+            for (int i = 0; i < worker_thread_count; i++)
                 io_service_pool_.emplace_back(new boost::asio::io_service());
-            get_cached_date_str_pool_.resize(concurrency_);
-            task_timer_pool_.resize(concurrency_);
+            get_cached_date_str_pool_.resize(worker_thread_count);
+            task_timer_pool_.resize(worker_thread_count);
 
             std::vector<std::future<void>> v;
             std::atomic<int> init_count(0);
-            for (uint16_t i = 0; i < concurrency_; i++)
+            for (uint16_t i = 0; i < worker_thread_count; i++)
                 v.push_back(
                   std::async(
                     std::launch::async, [this, i, &init_count] {
@@ -137,8 +138,7 @@ namespace crow
             handler_->port(port_);
 
 
-            CROW_LOG_INFO << server_name_ << " server is running at " << (handler_->ssl_used() ? "https://" : "http://") << bindaddr_ << ":" << acceptor_.local_endpoint().port()
-                          << " using " << concurrency_ << " threads";
+            CROW_LOG_INFO << server_name_ << " server is running at " << (handler_->ssl_used() ? "https://" : "http://") << bindaddr_ << ":" << acceptor_.local_endpoint().port() << " using " << concurrency_ << " threads";
             CROW_LOG_INFO << "Call `app.loglevel(crow::LogLevel::Warning)` to hide Info level logs.";
 
             signals_.async_wait(
@@ -146,7 +146,7 @@ namespace crow
                   stop();
               });
 
-            while (concurrency_ != init_count)
+            while (worker_thread_count != init_count)
                 std::this_thread::yield();
 
             do_accept();
@@ -232,7 +232,7 @@ namespace crow
         boost::asio::deadline_timer tick_timer_;
 
         Handler* handler_;
-        uint16_t concurrency_{1};
+        uint16_t concurrency_{2};
         std::uint8_t timeout_;
         std::string server_name_;
         uint16_t port_;