diff --git a/libraries/SITL/SIM_Aircraft.cpp b/libraries/SITL/SIM_Aircraft.cpp
index 69693ffabb..f5290dfaa6 100644
--- a/libraries/SITL/SIM_Aircraft.cpp
+++ b/libraries/SITL/SIM_Aircraft.cpp
@@ -17,9 +17,9 @@
   parent class for aircraft simulators
 */
 
-#include <AP_HAL.h>
+#include <AP_HAL/AP_HAL.h>
 #if CONFIG_HAL_BOARD == HAL_BOARD_SITL
-#include <AP_Common.h>
+#include <AP_Common/AP_Common.h>
 #include "SIM_Aircraft.h"
 #include <unistd.h>
 #include <sys/time.h>
diff --git a/libraries/SITL/SIM_Aircraft.h b/libraries/SITL/SIM_Aircraft.h
index 00c638b250..32b680115e 100644
--- a/libraries/SITL/SIM_Aircraft.h
+++ b/libraries/SITL/SIM_Aircraft.h
@@ -21,8 +21,8 @@
 #define _SIM_AIRCRAFT_H
 
 #include "SITL.h"
-#include <AP_Common.h>
-#include <AP_Math.h>
+#include <AP_Common/AP_Common.h>
+#include <AP_Math/AP_Math.h>
 
 /*
   parent class for all simulator types
diff --git a/libraries/SITL/SIM_Balloon.cpp b/libraries/SITL/SIM_Balloon.cpp
index 22c9ad6567..9fe58cfe30 100644
--- a/libraries/SITL/SIM_Balloon.cpp
+++ b/libraries/SITL/SIM_Balloon.cpp
@@ -17,7 +17,7 @@
   balloon simulator class
 */
 
-#include <AP_HAL.h>
+#include <AP_HAL/AP_HAL.h>
 #if CONFIG_HAL_BOARD == HAL_BOARD_SITL
 #include "SIM_Balloon.h"
 #include <stdio.h>
diff --git a/libraries/SITL/SIM_CRRCSim.cpp b/libraries/SITL/SIM_CRRCSim.cpp
index cfa792107f..f3a910de6d 100644
--- a/libraries/SITL/SIM_CRRCSim.cpp
+++ b/libraries/SITL/SIM_CRRCSim.cpp
@@ -17,7 +17,7 @@
   simulator connector for ardupilot version of CRRCSim
 */
 
-#include <AP_HAL.h>
+#include <AP_HAL/AP_HAL.h>
 #if CONFIG_HAL_BOARD == HAL_BOARD_SITL
 #include "SIM_CRRCSim.h"
 #include <stdio.h>
diff --git a/libraries/SITL/SIM_CRRCSim.h b/libraries/SITL/SIM_CRRCSim.h
index 41dda74d4b..663701c4ae 100644
--- a/libraries/SITL/SIM_CRRCSim.h
+++ b/libraries/SITL/SIM_CRRCSim.h
@@ -21,7 +21,7 @@
 #define _SIM_CRRCSIM_H
 
 #include "SIM_Aircraft.h"
-#include <utility/Socket.h>
+#include <AP_HAL/utility/Socket.h>
 
 /*
   a CRRCSim simulator
diff --git a/libraries/SITL/SIM_Gazebo.cpp b/libraries/SITL/SIM_Gazebo.cpp
index fbf4194d49..353b4d73ca 100644
--- a/libraries/SITL/SIM_Gazebo.cpp
+++ b/libraries/SITL/SIM_Gazebo.cpp
@@ -17,7 +17,7 @@
   simulator connector for ardupilot version of Gazebo
 */
 
-#include <AP_HAL.h>
+#include <AP_HAL/AP_HAL.h>
 #if CONFIG_HAL_BOARD == HAL_BOARD_SITL
 #include "SIM_Gazebo.h"
 #include <stdio.h>
diff --git a/libraries/SITL/SIM_Gazebo.h b/libraries/SITL/SIM_Gazebo.h
index 93028ede20..7b64bc96bc 100644
--- a/libraries/SITL/SIM_Gazebo.h
+++ b/libraries/SITL/SIM_Gazebo.h
@@ -21,7 +21,7 @@
 #define _SIM_GAZEBO_H
 
 #include "SIM_Aircraft.h"
-#include <utility/Socket.h>
+#include <AP_HAL/utility/Socket.h>
 
 /*
   Gazebo simulator
diff --git a/libraries/SITL/SIM_Gimbal.h b/libraries/SITL/SIM_Gimbal.h
index a5e4a34ccb..92bd43f1ce 100644
--- a/libraries/SITL/SIM_Gimbal.h
+++ b/libraries/SITL/SIM_Gimbal.h
@@ -22,7 +22,7 @@
 
 #include "SIM_Aircraft.h"
 #if CONFIG_HAL_BOARD == HAL_BOARD_SITL
-#include <utility/Socket.h>
+#include <AP_HAL/utility/Socket.h>
 
 class Gimbal
 {
diff --git a/libraries/SITL/SIM_Helicopter.cpp b/libraries/SITL/SIM_Helicopter.cpp
index 1557d8bfcf..d693d7237f 100644
--- a/libraries/SITL/SIM_Helicopter.cpp
+++ b/libraries/SITL/SIM_Helicopter.cpp
@@ -17,7 +17,7 @@
   helicopter simulator class
 */
 
-#include <AP_HAL.h>
+#include <AP_HAL/AP_HAL.h>
 #if CONFIG_HAL_BOARD == HAL_BOARD_SITL
 #include "SIM_Helicopter.h"
 #include <stdio.h>
diff --git a/libraries/SITL/SIM_JSBSim.cpp b/libraries/SITL/SIM_JSBSim.cpp
index 9d9d542895..b4856c455e 100644
--- a/libraries/SITL/SIM_JSBSim.cpp
+++ b/libraries/SITL/SIM_JSBSim.cpp
@@ -17,7 +17,7 @@
   simulator connector for ardupilot version of JSBSim
 */
 
-#include <AP_HAL.h>
+#include <AP_HAL/AP_HAL.h>
 #if CONFIG_HAL_BOARD == HAL_BOARD_SITL
 
 #include "SIM_JSBSim.h"
diff --git a/libraries/SITL/SIM_JSBSim.h b/libraries/SITL/SIM_JSBSim.h
index dd6ae00745..894fd18f60 100644
--- a/libraries/SITL/SIM_JSBSim.h
+++ b/libraries/SITL/SIM_JSBSim.h
@@ -21,7 +21,7 @@
 #define _SIM_JSBSIM_H
 
 #include "SIM_Aircraft.h"
-#include <utility/Socket.h>
+#include <AP_HAL/utility/Socket.h>
 
 /*
   a Jsbsim simulator
diff --git a/libraries/SITL/SIM_Multicopter.cpp b/libraries/SITL/SIM_Multicopter.cpp
index 339ca51b4f..4c8f7fa863 100644
--- a/libraries/SITL/SIM_Multicopter.cpp
+++ b/libraries/SITL/SIM_Multicopter.cpp
@@ -17,7 +17,7 @@
   multicopter simulator class
 */
 
-#include <AP_HAL.h>
+#include <AP_HAL/AP_HAL.h>
 #if CONFIG_HAL_BOARD == HAL_BOARD_SITL
 #include "SIM_Multicopter.h"
 #include <stdio.h>
diff --git a/libraries/SITL/SIM_Rover.cpp b/libraries/SITL/SIM_Rover.cpp
index 2941321788..17833580cd 100644
--- a/libraries/SITL/SIM_Rover.cpp
+++ b/libraries/SITL/SIM_Rover.cpp
@@ -17,7 +17,7 @@
   rover simulator class
 */
 
-#include <AP_HAL.h>
+#include <AP_HAL/AP_HAL.h>
 #if CONFIG_HAL_BOARD == HAL_BOARD_SITL
 #include "SIM_Rover.h"
 #include <stdio.h>
diff --git a/libraries/SITL/SIM_last_letter.cpp b/libraries/SITL/SIM_last_letter.cpp
index 92fd978b03..9a0f26e4bd 100644
--- a/libraries/SITL/SIM_last_letter.cpp
+++ b/libraries/SITL/SIM_last_letter.cpp
@@ -17,7 +17,7 @@
   simulator connector for ardupilot version of last_letter
 */
 
-#include <AP_HAL.h>
+#include <AP_HAL/AP_HAL.h>
 #if CONFIG_HAL_BOARD == HAL_BOARD_SITL
 #include "SIM_last_letter.h"
 #include <stdio.h>
diff --git a/libraries/SITL/SIM_last_letter.h b/libraries/SITL/SIM_last_letter.h
index 40bfa1b518..cbae765efe 100644
--- a/libraries/SITL/SIM_last_letter.h
+++ b/libraries/SITL/SIM_last_letter.h
@@ -21,7 +21,7 @@
 #define _SIM_LAST_LETTER_H
 
 #include "SIM_Aircraft.h"
-#include <utility/Socket.h>
+#include <AP_HAL/utility/Socket.h>
 
 /*
   a last_letter simulator
diff --git a/libraries/SITL/SITL.cpp b/libraries/SITL/SITL.cpp
index 439bd42657..92aa605861 100644
--- a/libraries/SITL/SITL.cpp
+++ b/libraries/SITL/SITL.cpp
@@ -18,10 +18,10 @@
     SITL.cpp - software in the loop state
 */
 
-#include <AP_Common.h>
-#include <AP_HAL.h>
-#include <GCS_MAVLink.h>
-#include <SITL.h>
+#include <AP_Common/AP_Common.h>
+#include <AP_HAL/AP_HAL.h>
+#include <GCS_MAVLink/GCS_MAVLink.h>
+#include "SITL.h"
 
 extern const AP_HAL::HAL& hal;
 
diff --git a/libraries/SITL/SITL.h b/libraries/SITL/SITL.h
index 964d396cea..517236dbd7 100644
--- a/libraries/SITL/SITL.h
+++ b/libraries/SITL/SITL.h
@@ -3,11 +3,11 @@
 #ifndef __SITL_H__
 #define __SITL_H__
 
-#include <AP_Param.h>
-#include <AP_Common.h>
-#include <AP_Math.h>
-#include <GCS_MAVLink.h>
-#include <DataFlash.h>
+#include <AP_Param/AP_Param.h>
+#include <AP_Common/AP_Common.h>
+#include <AP_Math/AP_Math.h>
+#include <GCS_MAVLink/GCS_MAVLink.h>
+#include <DataFlash/DataFlash.h>
 
 struct PACKED sitl_fdm {
     // this is the packet sent by the simulator