diff --git a/libraries/AP_AHRS/AP_AHRS.cpp b/libraries/AP_AHRS/AP_AHRS.cpp
index aab7dee011..5d7e6c8eaf 100644
--- a/libraries/AP_AHRS/AP_AHRS.cpp
+++ b/libraries/AP_AHRS/AP_AHRS.cpp
@@ -14,8 +14,8 @@
   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
-#include <AP_AHRS.h>
-#include <AP_HAL.h>
+#include "AP_AHRS.h"
+#include <AP_HAL/AP_HAL.h>
 extern const AP_HAL::HAL& hal;
 
 #if AHRS_EKF_USE_ALWAYS
diff --git a/libraries/AP_AHRS/AP_AHRS.h b/libraries/AP_AHRS/AP_AHRS.h
index 792e9fe386..149ea5ed61 100644
--- a/libraries/AP_AHRS/AP_AHRS.h
+++ b/libraries/AP_AHRS/AP_AHRS.h
@@ -22,14 +22,14 @@
  *
  */
 
-#include <AP_Math.h>
+#include <AP_Math/AP_Math.h>
 #include <inttypes.h>
-#include <AP_Compass.h>
-#include <AP_Airspeed.h>
-#include <AP_GPS.h>
-#include <AP_InertialSensor.h>
-#include <AP_Baro.h>
-#include <AP_Param.h>
+#include <AP_Compass/AP_Compass.h>
+#include <AP_Airspeed/AP_Airspeed.h>
+#include <AP_GPS/AP_GPS.h>
+#include <AP_InertialSensor/AP_InertialSensor.h>
+#include <AP_Baro/AP_Baro.h>
+#include <AP_Param/AP_Param.h>
 
 #include "../AP_OpticalFlow/AP_OpticalFlow.h"
 
@@ -444,8 +444,8 @@ protected:
     uint8_t _active_accel_instance;
 };
 
-#include <AP_AHRS_DCM.h>
-#include <AP_AHRS_NavEKF.h>
+#include "AP_AHRS_DCM.h"
+#include "AP_AHRS_NavEKF.h"
 
 #if AP_AHRS_NAVEKF_AVAILABLE
 #define AP_AHRS_TYPE AP_AHRS_NavEKF
diff --git a/libraries/AP_AHRS/AP_AHRS_DCM.cpp b/libraries/AP_AHRS/AP_AHRS_DCM.cpp
index ecdb465217..432bda539e 100644
--- a/libraries/AP_AHRS/AP_AHRS_DCM.cpp
+++ b/libraries/AP_AHRS/AP_AHRS_DCM.cpp
@@ -21,8 +21,8 @@
   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
-#include <AP_AHRS.h>
-#include <AP_HAL.h>
+#include "AP_AHRS.h"
+#include <AP_HAL/AP_HAL.h>
 
 extern const AP_HAL::HAL& hal;
 
diff --git a/libraries/AP_AHRS/AP_AHRS_NavEKF.cpp b/libraries/AP_AHRS/AP_AHRS_NavEKF.cpp
index 7feaba56da..cfceadeb8a 100644
--- a/libraries/AP_AHRS/AP_AHRS_NavEKF.cpp
+++ b/libraries/AP_AHRS/AP_AHRS_NavEKF.cpp
@@ -18,9 +18,9 @@
  *  ArduPilot
  *
  */
-#include <AP_HAL.h>
-#include <AP_AHRS.h>
-#include <AP_Vehicle.h>
+#include <AP_HAL/AP_HAL.h>
+#include "AP_AHRS.h"
+#include <AP_Vehicle/AP_Vehicle.h>
 
 #if AP_AHRS_NAVEKF_AVAILABLE
 
diff --git a/libraries/AP_AHRS/AP_AHRS_NavEKF.h b/libraries/AP_AHRS/AP_AHRS_NavEKF.h
index 7748abd2ba..8b20e4fae1 100644
--- a/libraries/AP_AHRS/AP_AHRS_NavEKF.h
+++ b/libraries/AP_AHRS/AP_AHRS_NavEKF.h
@@ -21,11 +21,11 @@
  *
  */
 
-#include <AP_HAL.h>
-#include <AP_AHRS.h>
+#include <AP_HAL/AP_HAL.h>
+#include "AP_AHRS.h"
 
 #if HAL_CPU_CLASS >= HAL_CPU_CLASS_150
-#include <AP_NavEKF.h>
+#include <AP_NavEKF/AP_NavEKF.h>
 
 #define AP_AHRS_NAVEKF_AVAILABLE 1
 #define AP_AHRS_NAVEKF_SETTLE_TIME_MS 20000     // time in milliseconds the ekf needs to settle after being started
diff --git a/libraries/AP_AHRS/examples/AHRS_Test/AHRS_Test.cpp b/libraries/AP_AHRS/examples/AHRS_Test/AHRS_Test.cpp
index 966d7e2458..b22e7c2000 100644
--- a/libraries/AP_AHRS/examples/AHRS_Test/AHRS_Test.cpp
+++ b/libraries/AP_AHRS/examples/AHRS_Test/AHRS_Test.cpp
@@ -4,44 +4,44 @@
 // Simple test for the AP_AHRS interface
 //
 
-#include <AP_HAL.h>
-#include <AP_Common.h>
-#include <AP_Progmem.h>
-#include <AP_Math.h>
-#include <AP_Param.h>
-#include <AP_InertialSensor.h>
-#include <AP_ADC.h>
-#include <AP_ADC_AnalogSource.h>
-#include <AP_Baro.h>            // ArduPilot Mega Barometer Library
-#include <AP_GPS.h>
-#include <AP_AHRS.h>
-#include <AP_Compass.h>
-#include <AP_Declination.h>
-#include <AP_Airspeed.h>
-#include <AP_Baro.h>
-#include <GCS_MAVLink.h>
-#include <AP_Mission.h>
-#include <StorageManager.h>
-#include <AP_Terrain.h>
-#include <Filter.h>
-#include <SITL.h>
-#include <AP_Buffer.h>
-#include <AP_Notify.h>
-#include <AP_Vehicle.h>
-#include <DataFlash.h>
-#include <AP_NavEKF.h>
-#include <AP_Rally.h>
-#include <AP_Scheduler.h>
+#include <AP_HAL/AP_HAL.h>
+#include <AP_Common/AP_Common.h>
+#include <AP_Progmem/AP_Progmem.h>
+#include <AP_Math/AP_Math.h>
+#include <AP_Param/AP_Param.h>
+#include <AP_InertialSensor/AP_InertialSensor.h>
+#include <AP_ADC/AP_ADC.h>
+#include <AP_ADC_AnalogSource/AP_ADC_AnalogSource.h>
+#include <AP_Baro/AP_Baro.h>            // ArduPilot Mega Barometer Library
+#include <AP_GPS/AP_GPS.h>
+#include <AP_AHRS/AP_AHRS.h>
+#include <AP_Compass/AP_Compass.h>
+#include <AP_Declination/AP_Declination.h>
+#include <AP_Airspeed/AP_Airspeed.h>
+#include <AP_Baro/AP_Baro.h>
+#include <GCS_MAVLink/GCS_MAVLink.h>
+#include <AP_Mission/AP_Mission.h>
+#include <StorageManager/StorageManager.h>
+#include <AP_Terrain/AP_Terrain.h>
+#include <Filter/Filter.h>
+#include <SITL/SITL.h>
+#include <AP_Buffer/AP_Buffer.h>
+#include <AP_Notify/AP_Notify.h>
+#include <AP_Vehicle/AP_Vehicle.h>
+#include <DataFlash/DataFlash.h>
+#include <AP_NavEKF/AP_NavEKF.h>
+#include <AP_Rally/AP_Rally.h>
+#include <AP_Scheduler/AP_Scheduler.h>
 
-#include <AP_HAL_AVR.h>
-#include <AP_HAL_SITL.h>
-#include <AP_HAL_Empty.h>
-#include <AP_HAL_Linux.h>
-#include <AP_HAL_PX4.h>
-#include <AP_BattMonitor.h>
-#include <AP_SerialManager.h>
-#include <RC_Channel.h>
-#include <AP_RangeFinder.h>
+#include <AP_HAL_AVR/AP_HAL_AVR.h>
+#include <AP_HAL_SITL/AP_HAL_SITL.h>
+#include <AP_HAL_Empty/AP_HAL_Empty.h>
+#include <AP_HAL_Linux/AP_HAL_Linux.h>
+#include <AP_HAL_PX4/AP_HAL_PX4.h>
+#include <AP_BattMonitor/AP_BattMonitor.h>
+#include <AP_SerialManager/AP_SerialManager.h>
+#include <RC_Channel/RC_Channel.h>
+#include <AP_RangeFinder/AP_RangeFinder.h>
 
 const AP_HAL::HAL& hal = AP_HAL_BOARD_DRIVER;