diff --git a/libraries/AC_PrecLand/AC_PrecLand.cpp b/libraries/AC_PrecLand/AC_PrecLand.cpp
index cf23c85549..b2e2212239 100644
--- a/libraries/AC_PrecLand/AC_PrecLand.cpp
+++ b/libraries/AC_PrecLand/AC_PrecLand.cpp
@@ -1,7 +1,12 @@
+#include "AC_PrecLand_config.h"
+
+#if AC_PRECLAND_ENABLED
+
+#include "AC_PrecLand.h"
 #include <AP_HAL/AP_HAL.h>
 #include <AP_Scheduler/AP_Scheduler.h>
 #include <AP_AHRS/AP_AHRS.h>
-#include "AC_PrecLand.h"
+
 #include "AC_PrecLand_Backend.h"
 #include "AC_PrecLand_Companion.h"
 #include "AC_PrecLand_IRLock.h"
@@ -774,3 +779,5 @@ AC_PrecLand *ac_precland()
 }
 
 }
+
+#endif // AC_PRECLAND_ENABLED
diff --git a/libraries/AC_PrecLand/AC_PrecLand.h b/libraries/AC_PrecLand/AC_PrecLand.h
index 2f804f59c9..397739c9f7 100644
--- a/libraries/AC_PrecLand/AC_PrecLand.h
+++ b/libraries/AC_PrecLand/AC_PrecLand.h
@@ -1,7 +1,11 @@
 #pragma once
 
-#include <AP_Math/AP_Math.h>
+#include "AC_PrecLand_config.h"
+
+#if AC_PRECLAND_ENABLED
+
 #include <GCS_MAVLink/GCS_MAVLink.h>
+#include <AP_Math/AP_Math.h>
 #include <stdint.h>
 #include "PosVelEKF.h"
 #include <AP_HAL/utility/RingBuffer.h>
@@ -231,3 +235,5 @@ private:
 namespace AP {
     AC_PrecLand *ac_precland();
 };
+
+#endif // AC_PRECLAND_ENABLED
diff --git a/libraries/AC_PrecLand/AC_PrecLand_Backend.h b/libraries/AC_PrecLand/AC_PrecLand_Backend.h
index d816a85d8d..41facd0deb 100644
--- a/libraries/AC_PrecLand/AC_PrecLand_Backend.h
+++ b/libraries/AC_PrecLand/AC_PrecLand_Backend.h
@@ -1,8 +1,13 @@
 #pragma once
 
+#include "AC_PrecLand_config.h"
+
+#if AC_PRECLAND_ENABLED
+
+#include "AC_PrecLand.h"
 #include <AP_Math/AP_Math.h>
 #include <AC_PID/AC_PID.h>
-#include "AC_PrecLand.h"
+
 
 class AC_PrecLand_Backend
 {
@@ -44,3 +49,5 @@ protected:
     const AC_PrecLand&  _frontend;          // reference to precision landing front end
     AC_PrecLand::precland_state &_state;    // reference to this instances state
 };
+
+#endif // AC_PRECLAND_ENABLED
diff --git a/libraries/AC_PrecLand/AC_PrecLand_Companion.cpp b/libraries/AC_PrecLand/AC_PrecLand_Companion.cpp
index e65ff1d686..51d46feb77 100644
--- a/libraries/AC_PrecLand/AC_PrecLand_Companion.cpp
+++ b/libraries/AC_PrecLand/AC_PrecLand_Companion.cpp
@@ -1,6 +1,10 @@
+#include "AC_PrecLand_config.h"
+
+#if AC_PRECLAND_COMPANION_ENABLED
+
+#include "AC_PrecLand_Companion.h"
 #include <AP_HAL/AP_HAL.h>
 #include <GCS_MAVLink/GCS.h>
-#include "AC_PrecLand_Companion.h"
 
 // perform any required initialisation of backend
 void AC_PrecLand_Companion::init()
@@ -73,3 +77,5 @@ void AC_PrecLand_Companion::handle_msg(const mavlink_landing_target_t &packet, u
     _los_meas_time_ms = timestamp_ms;
     _have_los_meas = true;
 }
+
+#endif // AC_PRECLAND_COMPANION_ENABLED
diff --git a/libraries/AC_PrecLand/AC_PrecLand_Companion.h b/libraries/AC_PrecLand/AC_PrecLand_Companion.h
index 67af707a9b..892a5aa1f8 100644
--- a/libraries/AC_PrecLand/AC_PrecLand_Companion.h
+++ b/libraries/AC_PrecLand/AC_PrecLand_Companion.h
@@ -1,7 +1,11 @@
 #pragma once
 
-#include <AP_Math/AP_Math.h>
+#include "AC_PrecLand_config.h"
+
+#if AC_PRECLAND_COMPANION_ENABLED
+
 #include "AC_PrecLand_Backend.h"
+#include <AP_Math/AP_Math.h>
 
 /*
  * AC_PrecLand_Companion - implements precision landing using target vectors provided
@@ -46,3 +50,6 @@ private:
     uint32_t            _los_meas_time_ms;      // system time in milliseconds when los was measured
     bool                _wrong_frame_msg_sent;
 };
+
+
+#endif // AC_PRECLAND_COMPANION_ENABLED
diff --git a/libraries/AC_PrecLand/AC_PrecLand_IRLock.cpp b/libraries/AC_PrecLand/AC_PrecLand_IRLock.cpp
index 04b1126621..e58bb52e82 100644
--- a/libraries/AC_PrecLand/AC_PrecLand_IRLock.cpp
+++ b/libraries/AC_PrecLand/AC_PrecLand_IRLock.cpp
@@ -1,5 +1,9 @@
-#include <AP_HAL/AP_HAL.h>
+#include "AC_PrecLand_config.h"
+
+#if AC_PRECLAND_IRLOCK_ENABLED
+
 #include "AC_PrecLand_IRLock.h"
+#include <AP_HAL/AP_HAL.h>
 
 // Constructor
 AC_PrecLand_IRLock::AC_PrecLand_IRLock(const AC_PrecLand& frontend, AC_PrecLand::precland_state& state)
@@ -50,3 +54,5 @@ uint32_t AC_PrecLand_IRLock::los_meas_time_ms() {
 bool AC_PrecLand_IRLock::have_los_meas() {
     return _have_los_meas;
 }
+
+#endif // AC_PRECLAND_IRLOCK_ENABLED
diff --git a/libraries/AC_PrecLand/AC_PrecLand_IRLock.h b/libraries/AC_PrecLand/AC_PrecLand_IRLock.h
index da2923b126..08831bc362 100644
--- a/libraries/AC_PrecLand/AC_PrecLand_IRLock.h
+++ b/libraries/AC_PrecLand/AC_PrecLand_IRLock.h
@@ -1,7 +1,12 @@
 #pragma once
 
-#include <AP_Math/AP_Math.h>
+#include "AC_PrecLand_config.h"
+
+#if AC_PRECLAND_IRLOCK_ENABLED
+
 #include <AC_PrecLand/AC_PrecLand_Backend.h>
+#include <AP_Math/AP_Math.h>
+
 #if CONFIG_HAL_BOARD == HAL_BOARD_SITL
  #include <AP_IRLock/AP_IRLock_SITL.h>
 #else
@@ -46,3 +51,5 @@ private:
     bool                _have_los_meas;         // true if there is a valid measurement from the camera
     uint32_t            _los_meas_time_ms;      // system time in milliseconds when los was measured
 };
+
+#endif // AC_PRECLAND_IRLOCK_ENABLED
diff --git a/libraries/AC_PrecLand/AC_PrecLand_SITL.cpp b/libraries/AC_PrecLand/AC_PrecLand_SITL.cpp
index b71a4d1c26..1d920818fb 100644
--- a/libraries/AC_PrecLand/AC_PrecLand_SITL.cpp
+++ b/libraries/AC_PrecLand/AC_PrecLand_SITL.cpp
@@ -1,7 +1,7 @@
 #include <AP_HAL/AP_HAL.h>
 #include "AC_PrecLand_SITL.h"
 
-#if CONFIG_HAL_BOARD == HAL_BOARD_SITL
+#if AC_PRECLAND_SITL_ENABLED
 
 #include "AP_AHRS/AP_AHRS.h"
 // init - perform initialisation of this backend
@@ -54,4 +54,4 @@ bool AC_PrecLand_SITL::get_los_body(Vector3f& ret) {
     return true;
 }
 
-#endif
+#endif  // AC_PRECLAND_SITL_ENABLED
diff --git a/libraries/AC_PrecLand/AC_PrecLand_SITL.h b/libraries/AC_PrecLand/AC_PrecLand_SITL.h
index ee6fd526ed..53b0c23aa6 100644
--- a/libraries/AC_PrecLand/AC_PrecLand_SITL.h
+++ b/libraries/AC_PrecLand/AC_PrecLand_SITL.h
@@ -1,8 +1,11 @@
 #pragma once
 
-#if CONFIG_HAL_BOARD == HAL_BOARD_SITL
-#include <AP_Math/AP_Math.h>
+#include "AC_PrecLand_config.h"
+
+#if AC_PRECLAND_SITL_ENABLED
+
 #include <AC_PrecLand/AC_PrecLand_Backend.h>
+#include <AP_Math/AP_Math.h>
 #include <SITL/SITL.h>
 
 /*
@@ -43,4 +46,4 @@ private:
     float               _distance_to_target;    // distance to target in meters
 };
 
-#endif
+#endif  // AC_PRECLAND_SITL_ENABLED
diff --git a/libraries/AC_PrecLand/AC_PrecLand_SITL_Gazebo.cpp b/libraries/AC_PrecLand/AC_PrecLand_SITL_Gazebo.cpp
index 2bf94759dc..95d331d75b 100644
--- a/libraries/AC_PrecLand/AC_PrecLand_SITL_Gazebo.cpp
+++ b/libraries/AC_PrecLand/AC_PrecLand_SITL_Gazebo.cpp
@@ -3,7 +3,7 @@
 
 extern const AP_HAL::HAL& hal;
 
-#if CONFIG_HAL_BOARD == HAL_BOARD_SITL
+#if AC_PRECLAND_SITL_GAZEBO_ENABLED
 
 // Constructor
 AC_PrecLand_SITL_Gazebo::AC_PrecLand_SITL_Gazebo(const AC_PrecLand& frontend, AC_PrecLand::precland_state& state)
@@ -55,4 +55,4 @@ bool AC_PrecLand_SITL_Gazebo::have_los_meas() {
     return _have_los_meas;
 }
 
-#endif
+#endif  // AC_PRECLAND_SITL_GAZEBO_ENABLED
diff --git a/libraries/AC_PrecLand/AC_PrecLand_SITL_Gazebo.h b/libraries/AC_PrecLand/AC_PrecLand_SITL_Gazebo.h
index e7f1ab06ed..dcddec958e 100644
--- a/libraries/AC_PrecLand/AC_PrecLand_SITL_Gazebo.h
+++ b/libraries/AC_PrecLand/AC_PrecLand_SITL_Gazebo.h
@@ -1,8 +1,11 @@
 #pragma once
 
-#if CONFIG_HAL_BOARD == HAL_BOARD_SITL
-#include <AP_Math/AP_Math.h>
+#include "AC_PrecLand_config.h"
+
+#if AC_PRECLAND_SITL_GAZEBO_ENABLED
+
 #include <AC_PrecLand/AC_PrecLand_Backend.h>
+#include <AP_Math/AP_Math.h>
 #include <AP_IRLock/AP_IRLock_SITL_Gazebo.h>
 
 /*
@@ -41,4 +44,4 @@ private:
     uint32_t            _los_meas_time_ms;      // system time in milliseconds when los was measured
 };
 
-#endif
+#endif  // AC_PRECLAND_SITL_GAZEBO_ENABLED
diff --git a/libraries/AC_PrecLand/AC_PrecLand_StateMachine.cpp b/libraries/AC_PrecLand/AC_PrecLand_StateMachine.cpp
index e2d3615651..c456288ca2 100644
--- a/libraries/AC_PrecLand/AC_PrecLand_StateMachine.cpp
+++ b/libraries/AC_PrecLand/AC_PrecLand_StateMachine.cpp
@@ -1,5 +1,9 @@
-#include "AC_PrecLand_StateMachine.h"
+#include "AC_PrecLand_config.h"
+
+#if AC_PRECLAND_ENABLED
+
 #include <AC_PrecLand/AC_PrecLand.h>
+#include "AC_PrecLand_StateMachine.h"
 #include <AP_AHRS/AP_AHRS.h>
 #include <GCS_MAVLink/GCS.h>
 
@@ -274,3 +278,5 @@ AC_PrecLand_StateMachine::FailSafeAction AC_PrecLand_StateMachine::get_failsafe_
     // should never reach here
     return FailSafeAction::DESCEND;
 }
+
+#endif // AC_PRECLAND_ENABLED
diff --git a/libraries/AC_PrecLand/AC_PrecLand_StateMachine.h b/libraries/AC_PrecLand/AC_PrecLand_StateMachine.h
index b72b0e8d72..8479be3c6a 100644
--- a/libraries/AC_PrecLand/AC_PrecLand_StateMachine.h
+++ b/libraries/AC_PrecLand/AC_PrecLand_StateMachine.h
@@ -1,5 +1,10 @@
 #pragma once
 
+#include "AC_PrecLand_config.h"
+
+#if AC_PRECLAND_ENABLED
+
+#include <AC_PrecLand/AC_PrecLand.h>
 #include <AP_Math/AP_Math.h>
 
 // This class constantly monitors what the status of the landing target is
@@ -101,3 +106,5 @@ private:
     uint32_t failsafe_start_ms; // timestamp of when failsafe was triggered
 
 };
+
+#endif // AC_PRECLAND_ENABLED
diff --git a/libraries/AC_PrecLand/AC_PrecLand_config.h b/libraries/AC_PrecLand/AC_PrecLand_config.h
new file mode 100644
index 0000000000..74a5043955
--- /dev/null
+++ b/libraries/AC_PrecLand/AC_PrecLand_config.h
@@ -0,0 +1,27 @@
+#pragma once
+
+#include <AP_HAL/AP_HAL_Boards.h>
+
+#ifndef AC_PRECLAND_ENABLED
+#define AC_PRECLAND_ENABLED 1
+#endif
+
+#ifndef AC_PRECLAND_BACKEND_DEFAULT_ENABLED
+#define AC_PRECLAND_BACKEND_DEFAULT_ENABLED AC_PRECLAND_ENABLED
+#endif
+
+#ifndef AC_PRECLAND_COMPANION_ENABLED
+#define AC_PRECLAND_COMPANION_ENABLED AC_PRECLAND_BACKEND_DEFAULT_ENABLED
+#endif
+
+#ifndef AC_PRECLAND_IRLOCK_ENABLED
+#define AC_PRECLAND_IRLOCK_ENABLED AC_PRECLAND_BACKEND_DEFAULT_ENABLED
+#endif
+
+#ifndef AC_PRECLAND_SITL_ENABLED
+#define AC_PRECLAND_SITL_ENABLED (AC_PRECLAND_BACKEND_DEFAULT_ENABLED && CONFIG_HAL_BOARD == HAL_BOARD_SITL)
+#endif
+
+#ifndef AC_PRECLAND_SITL_GAZEBO_ENABLED
+#define AC_PRECLAND_SITL_GAZEBO_ENABLED (AC_PRECLAND_BACKEND_DEFAULT_ENABLED && CONFIG_HAL_BOARD == HAL_BOARD_SITL)
+#endif