diff --git a/include/tclap/Arg.h b/include/tclap/Arg.h
index 03123a9..04d47f0 100644
--- a/include/tclap/Arg.h
+++ b/include/tclap/Arg.h
@@ -20,8 +20,8 @@
  *****************************************************************************/ 
 
 
-#ifndef __ARGUMENT_HH__
-#define __ARGUMENT_HH__
+#ifndef TCLAP_ARGUMENT_H
+#define TCLAP_ARGUMENT_H
 
 #include <string>
 #include <vector>
diff --git a/include/tclap/ArgException.h b/include/tclap/ArgException.h
index 632deeb..73f6f09 100644
--- a/include/tclap/ArgException.h
+++ b/include/tclap/ArgException.h
@@ -20,8 +20,8 @@
  *****************************************************************************/ 
 
 
-#ifndef __ARG_EXCEPTION_H__
-#define __ARG_EXCEPTION_H__
+#ifndef TCLAP_ARG_EXCEPTION_H
+#define TCLAP_ARG_EXCEPTION_H
 
 #include <string>
 #include <exception>
diff --git a/include/tclap/CmdLine.h b/include/tclap/CmdLine.h
index 03d8840..7df2940 100644
--- a/include/tclap/CmdLine.h
+++ b/include/tclap/CmdLine.h
@@ -19,8 +19,8 @@
  *  
  *****************************************************************************/ 
 
-#ifndef __CMDLINE_HH__
-#define __CMDLINE_HH__
+#ifndef TCLAP_CMDLINE_H
+#define TCLAP_CMDLINE_H
 
 #include <tclap/Arg.h>
 #include <tclap/SwitchArg.h>
diff --git a/include/tclap/CommandLine.h b/include/tclap/CommandLine.h
index a3fefae..45660ea 100644
--- a/include/tclap/CommandLine.h
+++ b/include/tclap/CommandLine.h
@@ -19,8 +19,8 @@
  *  
  *****************************************************************************/ 
 
-#ifndef __COMMANDLINE_HH__
-#define __COMMANDLINE_HH__
+#ifndef TCLAP_COMMANDLINE_H
+#define TCLAP_COMMANDLINE_H
 
 //
 // Explanation of dumb naming.  Originally this file was used as the generic
diff --git a/include/tclap/HelpVisitor.h b/include/tclap/HelpVisitor.h
index f3c7fbb..604ece4 100644
--- a/include/tclap/HelpVisitor.h
+++ b/include/tclap/HelpVisitor.h
@@ -19,8 +19,8 @@
  *  
  *****************************************************************************/ 
 
-#ifndef __HELP_VISITOR_H__
-#define __HELP_VISITOR_H__
+#ifndef TCLAP_HELP_VISITOR_H
+#define TCLAP_HELP_VISITOR_H
 
 #include <tclap/Visitor.h>
 
diff --git a/include/tclap/IgnoreRestVisitor.h b/include/tclap/IgnoreRestVisitor.h
index 5e30b36..e328649 100644
--- a/include/tclap/IgnoreRestVisitor.h
+++ b/include/tclap/IgnoreRestVisitor.h
@@ -20,8 +20,8 @@
  *****************************************************************************/ 
 
 
-#ifndef __IGNORE_REST_VISITOR_H__
-#define __IGNORE_REST_VISITOR_H__
+#ifndef TCLAP_IGNORE_REST_VISITOR_H
+#define TCLAP_IGNORE_REST_VISITOR_H
 
 #include <tclap/Visitor.h>
 #include <tclap/Arg.h>
diff --git a/include/tclap/MultiArg.h b/include/tclap/MultiArg.h
index a73abf1..cbe5b48 100644
--- a/include/tclap/MultiArg.h
+++ b/include/tclap/MultiArg.h
@@ -20,8 +20,8 @@
  *****************************************************************************/ 
 
 
-#ifndef __MULTIPLE_ARGUMENT_HH__
-#define __MULTIPLE_ARGUMENT_HH__
+#ifndef TCLAP_MULTIPLE_ARGUMENT_H
+#define TCLAP_MULTIPLE_ARGUMENT_H
 
 #include <string>
 #include <vector>
diff --git a/include/tclap/PrintSensibly.h b/include/tclap/PrintSensibly.h
index 15b2692..577ef88 100644
--- a/include/tclap/PrintSensibly.h
+++ b/include/tclap/PrintSensibly.h
@@ -19,8 +19,8 @@
  *  
  *****************************************************************************/ 
 
-#ifndef __PRINTSENSIBLY_HH__
-#define __PRINTSENSIBLY_HH__
+#ifndef TCLAP_PRINTSENSIBLY_H
+#define TCLAP_PRINTSENSIBLY_H
 
 #include <ostream>
 #include <algorithm>
diff --git a/include/tclap/SwitchArg.h b/include/tclap/SwitchArg.h
index a4aa708..a7265f9 100644
--- a/include/tclap/SwitchArg.h
+++ b/include/tclap/SwitchArg.h
@@ -20,8 +20,8 @@
  *****************************************************************************/ 
 
 
-#ifndef __SWITCH_ARG_HH__
-#define __SWITCH_ARG_HH__
+#ifndef TCLAP_SWITCH_ARG_H
+#define TCLAP_SWITCH_ARG_H
 
 #include <string>
 #include <vector>
diff --git a/include/tclap/UnlabeledMultiArg.h b/include/tclap/UnlabeledMultiArg.h
index 033c97e..0a4be9e 100644
--- a/include/tclap/UnlabeledMultiArg.h
+++ b/include/tclap/UnlabeledMultiArg.h
@@ -20,8 +20,8 @@
  *****************************************************************************/ 
 
 
-#ifndef __MULTIPLE_UNLABELED_ARGUMENT_HH__
-#define __MULTIPLE_UNLABELED_ARGUMENT_HH__
+#ifndef TCLAP_MULTIPLE_UNLABELED_ARGUMENT_H
+#define TCLAP_MULTIPLE_UNLABELED_ARGUMENT_H
 
 #include <string>
 #include <vector>
diff --git a/include/tclap/UnlabeledValueArg.h b/include/tclap/UnlabeledValueArg.h
index b1660ce..d7b31dc 100644
--- a/include/tclap/UnlabeledValueArg.h
+++ b/include/tclap/UnlabeledValueArg.h
@@ -20,8 +20,8 @@
  *****************************************************************************/ 
 
 
-#ifndef __UNLABELED_VALUE_ARGUMENT_HH__
-#define __UNLABELED_VALUE_ARGUMENT_HH__
+#ifndef TCLAP_UNLABELED_VALUE_ARGUMENT_H
+#define TCLAP_UNLABELED_VALUE_ARGUMENT_H
 
 #include <string>
 #include <vector>
diff --git a/include/tclap/ValueArg.h b/include/tclap/ValueArg.h
index c7895e6..4f5b643 100644
--- a/include/tclap/ValueArg.h
+++ b/include/tclap/ValueArg.h
@@ -20,8 +20,8 @@
  *****************************************************************************/ 
 
 
-#ifndef __VALUE_ARGUMENT_HH__
-#define __VALUE_ARGUMENT_HH__
+#ifndef TCLAP_VALUE_ARGUMENT_H
+#define TCLAP_VALUE_ARGUMENT_H
 
 #include <string>
 #include <vector>
diff --git a/include/tclap/VersionVisitor.h b/include/tclap/VersionVisitor.h
index 4f5f4e3..744a910 100644
--- a/include/tclap/VersionVisitor.h
+++ b/include/tclap/VersionVisitor.h
@@ -20,8 +20,8 @@
  *****************************************************************************/ 
 
 
-#ifndef __VERSION_VISITOR_H__
-#define __VERSION_VISITOR_H__
+#ifndef TCLAP_VERSION_VISITOR_H
+#define TCLAP_VERSION_VISITOR_H
 
 #include <tclap/Visitor.h>
 
diff --git a/include/tclap/Visitor.h b/include/tclap/Visitor.h
index ef84aec..746e2de 100644
--- a/include/tclap/Visitor.h
+++ b/include/tclap/Visitor.h
@@ -20,8 +20,8 @@
  *****************************************************************************/ 
 
 
-#ifndef __VISITOR_H__
-#define __VISITOR_H__
+#ifndef TCLAP_VISITOR_H
+#define TCLAP_VISITOR_H
 
 namespace TCLAP {
 
diff --git a/include/tclap/XorHandler.h b/include/tclap/XorHandler.h
index 567f68d..46ac223 100644
--- a/include/tclap/XorHandler.h
+++ b/include/tclap/XorHandler.h
@@ -19,8 +19,8 @@
  *  
  *****************************************************************************/ 
 
-#ifndef __ORHANDLER_HH__
-#define __ORHANDLER_HH__
+#ifndef TCLAP_XORHANDLER_H
+#define TCLAP_XORHANDLER_H
 
 #include <tclap/Arg.h>
 #include <tclap/PrintSensibly.h>