diff --git a/bin/mbus-serial-request-data-multi-reply.c b/bin/mbus-serial-request-data-multi-reply.c
index d0c06d1..e9c74a8 100755
--- a/bin/mbus-serial-request-data-multi-reply.c
+++ b/bin/mbus-serial-request-data-multi-reply.c
@@ -106,13 +106,13 @@ main(int argc, char **argv)
 
     if (mbus_connect(handle) == -1)
     {
-        printf("Failed to setup connection to M-bus gateway\n");
+        fprintf(stderr,"Failed to setup connection to M-bus gateway\n");
         return 1;
     }
 
     if (mbus_serial_set_baudrate(handle, baudrate) == -1)
     {
-        printf("Failed to set baud rate.\n");
+        fprintf(stderr,"Failed to set baud rate.\n");
         return 1;
     }
     
diff --git a/bin/mbus-serial-request-data.c b/bin/mbus-serial-request-data.c
index 74dacf3..a250781 100755
--- a/bin/mbus-serial-request-data.c
+++ b/bin/mbus-serial-request-data.c
@@ -77,13 +77,13 @@ main(int argc, char **argv)
 
     if (mbus_connect(handle) == -1)
     {
-        printf("Failed to setup connection to M-bus gateway\n");
+        fprintf(stderr,"Failed to setup connection to M-bus gateway\n");
         return 1;
     }
 
     if (mbus_serial_set_baudrate(handle, baudrate) == -1)
     {
-        printf("Failed to set baud rate.\n");
+        fprintf(stderr,"Failed to set baud rate.\n");
         return 1;
     }
 
diff --git a/bin/mbus-serial-scan-secondary.c b/bin/mbus-serial-scan-secondary.c
index b382f4a..e4ae295 100755
--- a/bin/mbus-serial-scan-secondary.c
+++ b/bin/mbus-serial-scan-secondary.c
@@ -144,7 +144,7 @@ main(int argc, char **argv)
 
     if (mbus_connect(handle) == -1)
     {
-        printf("Failed to setup connection to M-bus gateway\n");
+        fprintf(stderr,"Failed to setup connection to M-bus gateway\n");
         free(addr_mask);
         return 1;
     }
diff --git a/bin/mbus-serial-scan.c b/bin/mbus-serial-scan.c
index 586511d..ad06cdd 100755
--- a/bin/mbus-serial-scan.c
+++ b/bin/mbus-serial-scan.c
@@ -31,7 +31,7 @@ int ping_address(mbus_handle *handle, mbus_frame *reply, int address)
     
         if (mbus_send_ping_frame(handle, address, 0) == -1)
         {
-            printf("Scan failed. Could not send ping frame: %s\n", mbus_error_str());
+            fprintf(stderr,"Scan failed. Could not send ping frame: %s\n", mbus_error_str());
             return MBUS_RECV_RESULT_ERROR;
         } 
      
@@ -103,7 +103,7 @@ main(int argc, char **argv)
     }
     else
     {
-        printf("usage: %s [-d] [-b BAUDRATE] [-r RETRIES] device\n", argv[0]);
+        fprintf(stderr,"usage: %s [-d] [-b BAUDRATE] [-r RETRIES] device\n", argv[0]);
         return 0;
     }
     
@@ -115,25 +115,25 @@ main(int argc, char **argv)
     
     if ((handle = mbus_context_serial(device)) == NULL)
     {
-        printf("Scan failed: Could not initialize M-Bus context: %s\n",  mbus_error_str());
+        fprintf(stderr,"Scan failed: Could not initialize M-Bus context: %s\n",  mbus_error_str());
         return 1;
     }
 
     if (mbus_connect(handle) == -1)
     {
-        printf("Scan failed: Could not setup connection to M-bus gateway: %s\n", mbus_error_str());
+        fprintf(stderr,"Scan failed: Could not setup connection to M-bus gateway: %s\n", mbus_error_str());
         return 1;
     }
     
     if (mbus_context_set_option(handle, MBUS_OPTION_MAX_RETRY, retries) == -1)
     {
-        printf("Failed to set retry count\n");
+        fprintf(stderr,"Failed to set retry count\n");
         return 1;
     }
 
     if (mbus_serial_set_baudrate(handle, baudrate) == -1)
     {
-        printf("Failed to set baud rate.\n");
+        fprintf(stderr,"Failed to set baud rate.\n");
         return 1;
     }
 
diff --git a/bin/mbus-serial-select-secondary.c b/bin/mbus-serial-select-secondary.c
index 87f5b80..343a22a 100755
--- a/bin/mbus-serial-select-secondary.c
+++ b/bin/mbus-serial-select-secondary.c
@@ -51,7 +51,7 @@ main(int argc, char **argv)
  
     if (mbus_is_secondary_address(addr) == 0)
     {
-        printf("Misformatted secondary address. Must be 16 character HEX number.\n");
+        fprintf(stderr,"Misformatted secondary address. Must be 16 character HEX number.\n");
         return 1;
     }
 
@@ -63,19 +63,19 @@ main(int argc, char **argv)
 
     if (mbus_connect(handle) == -1)
     {
-        printf("Failed to setup connection to M-bus gateway\n");
+        fprintf(stderr,"Failed to setup connection to M-bus gateway\n");
         return 1;
     }
 
     if (mbus_serial_set_baudrate(handle, baudrate) == -1)
     {
-        printf("Failed to set baud rate.\n");
+        fprintf(stderr,"Failed to set baud rate.\n");
         return 1;
     }
 
     if (mbus_send_select_frame(handle, addr) == -1)
     {
-        printf("Failed to send selection frame: %s\n", mbus_error_str());
+        fprintf(stderr,"Failed to send selection frame: %s\n", mbus_error_str());
         return 1; 
     }
 
@@ -83,13 +83,13 @@ main(int argc, char **argv)
 
     if (ret == MBUS_RECV_RESULT_TIMEOUT)
     {
-        printf("No reply from device with secondary address %s: %s\n", argv[2], mbus_error_str());
+        fprintf(stderr,"No reply from device with secondary address %s: %s\n", argv[2], mbus_error_str());
         return 1;
     }    
 
     if (ret == MBUS_RECV_RESULT_INVALID)
     {
-        printf("Invalid reply from %s: The address address probably match more than one device: %s\n", argv[2], mbus_error_str());
+        fprintf(stderr,"Invalid reply from %s: The address address probably match more than one device: %s\n", argv[2], mbus_error_str());
         return 1;
     }
 
@@ -97,13 +97,13 @@ main(int argc, char **argv)
     {
         if (mbus_send_request_frame(handle, MBUS_ADDRESS_NETWORK_LAYER) == -1)
 	    {
-            printf("Failed to send request to selected secondary device: %s\n", mbus_error_str());
+            fprintf(stderr,"Failed to send request to selected secondary device: %s\n", mbus_error_str());
             return 1;
         }
 
         if (mbus_recv_frame(handle, &reply) != MBUS_RECV_RESULT_OK)
         {
-            printf("Failed to recieve reply from selected secondary device: %s\n", mbus_error_str());
+            fprintf(stderr,"Failed to recieve reply from selected secondary device: %s\n", mbus_error_str());
             return 1;
         }
 
@@ -115,7 +115,7 @@ main(int argc, char **argv)
     }
     else
     {
-        printf("Unknown reply:\n");
+        fprintf(stderr,"Unknown reply:\n");
         mbus_frame_print(&reply);
     }
  
diff --git a/bin/mbus-serial-switch-baudrate.c b/bin/mbus-serial-switch-baudrate.c
index b9186c4..c5c4849 100755
--- a/bin/mbus-serial-switch-baudrate.c
+++ b/bin/mbus-serial-switch-baudrate.c
@@ -56,19 +56,19 @@ main(int argc, char **argv)
 
     if (mbus_connect(handle) == -1)
     {
-        printf("Failed to setup connection to M-bus gateway\n");
+        fprintf(stderr,"Failed to setup connection to M-bus gateway\n");
         return 1;
     }
     
     if (mbus_serial_set_baudrate(handle, source_baudrate) == -1)
     {
-        printf("Failed to set baud rate.\n");
+        fprintf(stderr,"Failed to set baud rate.\n");
         return 1;
     }
 
     if (mbus_send_switch_baudrate_frame(handle, address, target_baudrate) == -1)
     {
-        printf("Failed to send switch baudrate frame: %s\n", mbus_error_str());
+        fprintf(stderr,"Failed to send switch baudrate frame: %s\n", mbus_error_str());
         return 1; 
     }
 
@@ -76,12 +76,12 @@ main(int argc, char **argv)
     
     if (ret == MBUS_RECV_RESULT_TIMEOUT)
     {
-        printf("No reply from device\n");
+        fprintf(stderr,"No reply from device\n");
         return 1;
     }
     else if (mbus_frame_type(&reply) != MBUS_FRAME_TYPE_ACK)
     {
-        printf("Unknown reply:\n");
+        fprintf(stderr,"Unknown reply:\n");
         mbus_frame_print(&reply);
     }
     else
diff --git a/bin/mbus-tcp-scan.c b/bin/mbus-tcp-scan.c
index 1adc93a..38ecb75 100755
--- a/bin/mbus-tcp-scan.c
+++ b/bin/mbus-tcp-scan.c
@@ -31,7 +31,7 @@ int ping_address(mbus_handle *handle, mbus_frame *reply, int address)
     
         if (mbus_send_ping_frame(handle, address, 0) == -1)
         {
-            printf("Scan failed. Could not send ping frame: %s\n", mbus_error_str());
+            fprintf(stderr,"Scan failed. Could not send ping frame: %s\n", mbus_error_str());
             return MBUS_RECV_RESULT_ERROR;
         } 
      
@@ -83,7 +83,7 @@ main(int argc, char **argv)
     }
     else
     {
-        printf("usage: %s [-d] [-r RETRIES] host port\n", argv[0]);
+        fprintf(stderr,"usage: %s [-d] [-r RETRIES] host port\n", argv[0]);
         return 0;
     }
     
@@ -95,19 +95,19 @@ main(int argc, char **argv)
      
     if ((handle = mbus_context_tcp(host, port)) == NULL)
     {
-        printf("Scan failed: Could not initialize M-Bus context: %s\n",  mbus_error_str());
+        fprintf(stderr,"Scan failed: Could not initialize M-Bus context: %s\n",  mbus_error_str());
         return 1;
     }
 
     if (mbus_connect(handle) == -1)
     {
-        printf("Scan failed: Could not setup connection to M-bus gateway: %s\n", mbus_error_str());
+        fprintf(stderr,"Scan failed: Could not setup connection to M-bus gateway: %s\n", mbus_error_str());
         return 1;
     }
     
     if (mbus_context_set_option(handle, MBUS_OPTION_MAX_RETRY, retries) == -1)
     {
-        printf("Failed to set retry count\n");
+        fprintf(stderr,"Failed to set retry count\n");
         return 1;
     }
 
diff --git a/bin/mbus-tcp-select-secondary.c b/bin/mbus-tcp-select-secondary.c
index 904bd27..5966ff5 100755
--- a/bin/mbus-tcp-select-secondary.c
+++ b/bin/mbus-tcp-select-secondary.c
@@ -27,7 +27,7 @@ main(int argc, char **argv)
 
     if (argc != 4)
     {
-        printf("usage: %s host port secondary-mbus-address\n", argv[0]);
+        fprintf(stderr,"usage: %s host port secondary-mbus-address\n", argv[0]);
         return 0;
     }
  
@@ -42,7 +42,7 @@ main(int argc, char **argv)
 
     if (mbus_is_secondary_address(addr) == 0)
     {
-        printf("Misformatted secondary address. Must be 16 character HEX number.\n");
+        fprintf(stderr,"Misformatted secondary address. Must be 16 character HEX number.\n");
         return 1;
     }
 
@@ -60,7 +60,7 @@ main(int argc, char **argv)
 
     if (mbus_send_select_frame(handle, addr) == -1)
     {
-        printf("Failed to send selection frame: %s\n", mbus_error_str());
+        fprintf(stderr,"Failed to send selection frame: %s\n", mbus_error_str());
         return 1; 
     }
 
@@ -68,13 +68,13 @@ main(int argc, char **argv)
 
     if (ret == MBUS_RECV_RESULT_TIMEOUT)
     {
-        printf("No reply from device with secondary address %s: %s\n", argv[3], mbus_error_str());
+        fprintf(stderr,"No reply from device with secondary address %s: %s\n", argv[3], mbus_error_str());
         return 1;
     }    
 
     if (ret == MBUS_RECV_RESULT_INVALID)
     {
-        printf("Invalid reply from %s: The address address probably match more than one device: %s\n", argv[3], mbus_error_str());
+        fprintf(stderr,"Invalid reply from %s: The address address probably match more than one device: %s\n", argv[3], mbus_error_str());
         return 1;
     }
 
@@ -82,13 +82,13 @@ main(int argc, char **argv)
     {
         if (mbus_send_request_frame(handle, MBUS_ADDRESS_NETWORK_LAYER) == -1)
 	    {
-            printf("Failed to send request to selected secondary device: %s\n", mbus_error_str());
+            fprintf(stderr,"Failed to send request to selected secondary device: %s\n", mbus_error_str());
             return 1;
         }
 
         if (mbus_recv_frame(handle, &reply) != MBUS_RECV_RESULT_OK)
         {
-            printf("Failed to recieve reply from selected secondary device: %s\n", mbus_error_str());
+            fprintf(stderr,"Failed to recieve reply from selected secondary device: %s\n", mbus_error_str());
             return 1;
         }
 
@@ -100,7 +100,7 @@ main(int argc, char **argv)
     }
     else
     {
-        printf("Unknown reply:\n");
+        fprintf(stderr,"Unknown reply:\n");
         mbus_frame_print(&reply);
     }