diff --git a/include/fpu.h b/include/fpu.h
index 409b1520..d1111a21 100644
--- a/include/fpu.h
+++ b/include/fpu.h
@@ -16,10 +16,12 @@
  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  */
 
-#ifndef __FPU_H
-#define __FPU_H
+#ifndef DOSBOX_FPU_H
+#define DOSBOX_FPU_H
 
+#ifndef DOSBOX_MEM_H
 #include "mem.h"
+#endif
 
 void FPU_ESC0_Normal(Bitu rm);
 void FPU_ESC0_EA(Bitu func,PhysPt ea);
diff --git a/include/hardware.h b/include/hardware.h
index 0a72c1ca..5b5079b8 100644
--- a/include/hardware.h
+++ b/include/hardware.h
@@ -16,8 +16,8 @@
  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  */
 
-#ifndef _HARDWARE_H_
-#define _HARDWARE_H_
+#ifndef DOSBOX_HARDWARE_H
+#define DOSBOX_HARDWARE_H
 
 #include <stdio.h>
 
@@ -33,5 +33,3 @@ FILE * OpenCaptureFile(const char * type,const char * ext);
 
 
 #endif
-
-
diff --git a/include/ipx.h b/include/ipx.h
index 43f6372c..c9ff29a7 100644
--- a/include/ipx.h
+++ b/include/ipx.h
@@ -16,8 +16,8 @@
  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  */
 
-#ifndef _IPX_H_
-#define _IPX_H_
+#ifndef DOSBOX_IPX_H
+#define DOSBOX_IPX_H
 
 // In Use Flag codes
 #define USEFLAG_AVAILABLE  0x00
@@ -89,4 +89,3 @@ void PackIP(IPaddress ipAddr, PackedIP *ipPack);
 #endif
 
 #endif
-
diff --git a/include/ipxserver.h b/include/ipxserver.h
index c8e70126..54805d1e 100644
--- a/include/ipxserver.h
+++ b/include/ipxserver.h
@@ -16,8 +16,8 @@
  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  */
 
-#ifndef _IPXSERVER_H_
-#define _IPXSERVER_H_
+#ifndef DOSBOX_IPXSERVER_H_
+#define DOSBOX_IPXSERVER_H_
 
 #if C_IPX
 
@@ -47,4 +47,3 @@ Bit8u packetCRC(Bit8u *buffer, Bit16u bufSize);
 #endif
 
 #endif
-
diff --git a/include/keyboard.h b/include/keyboard.h
index 195c3d06..9fb7fa29 100644
--- a/include/keyboard.h
+++ b/include/keyboard.h
@@ -16,8 +16,8 @@
  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  */
 
-#ifndef _KEYBOARD_H_
-#define _KEYBOARD_H_
+#ifndef DOSBOX_KEYBOARD_H
+#define DOSBOX_KEYBOARD_H
 
 enum KBD_KEYS {
 	KBD_NONE,
diff --git a/include/mapper.h b/include/mapper.h
index ca65cd92..78bddc00 100644
--- a/include/mapper.h
+++ b/include/mapper.h
@@ -16,8 +16,8 @@
  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  */
 
-#ifndef MAPPER_H_
-#define MAPPER_H_
+#ifndef DOSBOX_MAPPER_H
+#define DOSBOX_MAPPER_H
 
 enum MapKeys {
 	MK_f1,MK_f2,MK_f3,MK_f4,MK_f5,MK_f6,MK_f7,MK_f8,MK_f9,MK_f10,MK_f11,MK_f12,
diff --git a/include/mouse.h b/include/mouse.h
index e8338381..99c7ffd5 100644
--- a/include/mouse.h
+++ b/include/mouse.h
@@ -16,10 +16,10 @@
  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  */
 
-/* $Id: mouse.h,v 1.8 2005-02-10 10:20:47 qbix79 Exp $ */
+/* $Id: mouse.h,v 1.9 2005-03-24 10:32:09 qbix79 Exp $ */
 
-#ifndef _MOUSE_H_
-#define _MOUSE_H_
+#ifndef DOSBOX_MOUSE_H
+#define DOSBOX_MOUSE_H
 
 void Mouse_ShowCursor(void);
 void Mouse_HideCursor(void);
@@ -35,5 +35,4 @@ void Mouse_ButtonReleased(Bit8u button);
 void Mouse_AutoLock(bool enable);
 void Mouse_NewVideoMode(void);
 
-#endif
-
+#endif
diff --git a/include/paging.h b/include/paging.h
index 19861ccc..c11e39c1 100644
--- a/include/paging.h
+++ b/include/paging.h
@@ -16,13 +16,17 @@
  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  */
 
-/* $Id: paging.h,v 1.14 2005-02-10 10:20:47 qbix79 Exp $ */
+/* $Id: paging.h,v 1.15 2005-03-24 10:32:09 qbix79 Exp $ */
 
-#ifndef _PAGING_H_
-#define _PAGING_H_
+#ifndef DOSBOX_PAGING_H
+#define DOSBOX_PAGING_H
 
+#ifndef DOSBOX_DOSBOX_H
 #include "dosbox.h"
+#endif
+#ifndef DOSBOX_MEM_H
 #include "mem.h"
+#endif
 
 class PageDirectory;
 
diff --git a/include/pic.h b/include/pic.h
index a851aa19..6440ca22 100644
--- a/include/pic.h
+++ b/include/pic.h
@@ -16,8 +16,8 @@
  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  */
 
-#ifndef __PIC_H
-#define __PIC_H
+#ifndef DOSBOX_PIC_H
+#define DOSBOX_PIC_H
 
 
 /* CPU Cycle Timing */
@@ -60,4 +60,3 @@ void PIC_RemoveEvents(PIC_EventHandler handler);
 
 void PIC_SetIRQMask(Bitu irq, bool masked);
 #endif
-
diff --git a/include/regs.h b/include/regs.h
index b9ab3016..98319c28 100644
--- a/include/regs.h
+++ b/include/regs.h
@@ -16,10 +16,12 @@
  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  */
 
-#if !defined __REGS_H
-#define __REGS_H
+#ifndef DOSBOX_REGS_H
+#define DOSBOX_REGS_H
 
-#include <mem.h>
+#ifndef DOSBOX_MEM_H
+#include "mem.h"
+#endif
 
 #define FLAG_CF		0x00000001
 #define FLAG_PF		0x00000004
@@ -165,4 +167,3 @@ enum {
 #define reg_flags cpu_regs.flags
 
 #endif
-
diff --git a/include/render.h b/include/render.h
index 0f9169da..de42225e 100644
--- a/include/render.h
+++ b/include/render.h
@@ -16,8 +16,8 @@
  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  */
 
-#ifndef __RENDER_H
-#define __RENDER_H
+#ifndef DOSBOX_RENDER_H
+#define DOSBOX_RENDER_H
 
 typedef void (* RENDER_Line_Handler)(const Bit8u * src);
 
@@ -29,4 +29,3 @@ extern RENDER_Line_Handler RENDER_DrawLine;
 
 
 #endif
-
diff --git a/include/timer.h b/include/timer.h
index 68e600f9..742348ea 100644
--- a/include/timer.h
+++ b/include/timer.h
@@ -16,8 +16,9 @@
  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  */
 
-#ifndef _TIMER_H_
-#define _TIMER_H_
+#ifndef DOSBOX_TIMER_H
+#define DOSBOX_TIMER_H
+
 /* underlying clock rate in HZ */
 #include <SDL.h>
 
@@ -35,4 +36,3 @@ void TIMER_DelTickHandler(TIMER_TickHandler handler);
 void TIMER_AddTick(void);
 
 #endif
-
diff --git a/include/vga.h b/include/vga.h
index 98b1edb9..07c06bac 100644
--- a/include/vga.h
+++ b/include/vga.h
@@ -16,11 +16,12 @@
  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  */
 
-#ifndef VGA_H_
-#define VGA_H_
+#ifndef DOSBOX_VGA_H
+#define DOSBOX_VGA_H
 
-#include <mem.h>
+#ifndef DOSBOX_DOSBOX_H
 #include "dosbox.h"
+#endif
 
 enum VGAModes {
 	M_CGA2,M_CGA4,
@@ -360,4 +361,3 @@ extern Bit32u Expand16BigTable[0x10000];
 
 
 #endif
-
diff --git a/include/video.h b/include/video.h
index 8846493b..08bbc5bf 100644
--- a/include/video.h
+++ b/include/video.h
@@ -16,8 +16,8 @@
  *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  */
 
-#ifndef __VIDEO_H
-#define __VIDEO_H
+#ifndef DOSBOX_VIDEO_H
+#define DOSBOX_VIDEO_H
 
 typedef void (* GFX_ResetCallBack)(void);
 
@@ -67,4 +67,3 @@ void GFX_CaptureMouse(void);
 extern bool mouselocked; //true if mouse is confined to window
 
 #endif
-