diff --git a/Makefile b/Makefile
index ffe440b..856451f 100644
--- a/Makefile
+++ b/Makefile
@@ -14,7 +14,7 @@ OBJS = fped.o expr.o coord.o obj.o delete.o inst.o util.o error.o \
        unparse.o dump.o meas.o \
        cpp.o lex.yy.o y.tab.o \
        gui.o gui_util.o gui_style.o gui_inst.o gui_status.o gui_canvas.o \
-       gui_tools.o gui_over.o gui_meas.o gui_frame.o
+       gui_tool.o gui_over.o gui_meas.o gui_frame.o
 
 XPMS = point.xpm delete.xpm vec.xpm frame.xpm frame_locked.xpm frame_ready.xpm \
        line.xpm rect.xpm pad.xpm circ.xpm meas.xpm meas_x.xpm meas_y.xpm
@@ -95,7 +95,7 @@ y.tab.c y.tab.h: fpd.y
 y.tab.o:	y.tab.c
 		$(CC) -c $(CFLAGS) $(SLOPPY) y.tab.c
 
-gui_tools.o:	$(XPMS:%=icons/%)
+gui_tool.o:	$(XPMS:%=icons/%)
 
 # ----- Dependencies ----------------------------------------------------------
 
diff --git a/gui.c b/gui.c
index c88fac0..8e349c9 100644
--- a/gui.c
+++ b/gui.c
@@ -20,7 +20,7 @@
 #include "gui_style.h"
 #include "gui_status.h"
 #include "gui_canvas.h"
-#include "gui_tools.h"
+#include "gui_tool.h"
 #include "gui_frame.h"
 #include "gui.h"
 
diff --git a/gui_canvas.c b/gui_canvas.c
index 9ddb4dd..56fb9ae 100644
--- a/gui_canvas.c
+++ b/gui_canvas.c
@@ -22,7 +22,7 @@
 #include "gui_inst.h"
 #include "gui_style.h"
 #include "gui_status.h"
-#include "gui_tools.h"
+#include "gui_tool.h"
 #include "gui.h"
 #include "gui_canvas.h"
 
diff --git a/gui_frame.c b/gui_frame.c
index 3ccf2ce..01e89b1 100644
--- a/gui_frame.c
+++ b/gui_frame.c
@@ -23,7 +23,7 @@
 #include "gui_util.h"
 #include "gui_style.h"
 #include "gui_status.h"
-#include "gui_tools.h"
+#include "gui_tool.h"
 #include "gui.h"
 #include "gui_frame.h"
 
diff --git a/gui_meas.c b/gui_meas.c
index a6ad2c5..928a5db 100644
--- a/gui_meas.c
+++ b/gui_meas.c
@@ -14,7 +14,7 @@
 #include "util.h"
 #include "meas.h"
 #include "gui_canvas.h"
-#include "gui_tools.h"
+#include "gui_tool.h"
 #include "gui_meas.h"
 
 
diff --git a/gui_tools.c b/gui_tool.c
similarity index 99%
rename from gui_tools.c
rename to gui_tool.c
index f7e5ad4..67f787d 100644
--- a/gui_tools.c
+++ b/gui_tool.c
@@ -1,5 +1,5 @@
 /*
- * gui_tools.c - GUI, tool bar
+ * gui_tool.c - GUI, tool bar
  *
  * Written 2009 by Werner Almesberger
  * Copyright 2009 by Werner Almesberger
@@ -27,7 +27,7 @@
 #include "gui_status.h"
 #include "gui.h"
 #include "gui_meas.h"
-#include "gui_tools.h"
+#include "gui_tool.h"
 
 
 #include "icons/circ.xpm"
diff --git a/gui_tools.h b/gui_tool.h
similarity index 95%
rename from gui_tools.h
rename to gui_tool.h
index b65f5ad..97a7a81 100644
--- a/gui_tools.h
+++ b/gui_tool.h
@@ -1,5 +1,5 @@
 /*
- * gui_tools.h - GUI, tool bar
+ * gui_tool.h - GUI, tool bar
  *
  * Written 2009 by Werner Almesberger
  * Copyright 2009 by Werner Almesberger
@@ -11,8 +11,8 @@
  */
 
 
-#ifndef GUI_TOOLS_H
-#define	GUI_TOOLS_H
+#ifndef GUI_TOOL_H
+#define	GUI_TOOL_H
 
 #include <gtk/gtk.h>
 
@@ -75,4 +75,4 @@ void tool_reset(void);
 
 GtkWidget *gui_setup_tools(GdkDrawable *drawable);
 
-#endif /* !GUI_TOOLS_H */
+#endif /* !GUI_TOOL_H */
diff --git a/inst.c b/inst.c
index 455510c..28d1d33 100644
--- a/inst.c
+++ b/inst.c
@@ -22,7 +22,7 @@
 #include "delete.h"
 #include "gui_util.h"
 #include "gui_status.h"
-#include "gui_tools.h"
+#include "gui_tool.h"
 #include "gui_inst.h"
 #include "inst.h"