diff --git a/src/cmd/8l/obj.c b/src/cmd/8l/obj.c
index 82f4e47b7c0..c4732b6681f 100644
--- a/src/cmd/8l/obj.c
+++ b/src/cmd/8l/obj.c
@@ -168,7 +168,7 @@ main(int argc, char *argv[])
 		if(strcmp(goos, "freebsd") == 0)
 			HEADTYPE = 9;
 		else
-		if(strcmp(goos, "mingw") == 0)
+		if(strcmp(goos, "windows") == 0)
 			HEADTYPE = 10;
 		else
 		if(strcmp(goos, "pchw") == 0)
diff --git a/src/env.bash b/src/env.bash
index 6ab491ae439..2a63e648062 100644
--- a/src/env.bash
+++ b/src/env.bash
@@ -45,10 +45,10 @@ esac
 
 GOOS=${GOOS:-$(uname | tr A-Z a-z)}
 case "$GOOS" in
-darwin | freebsd | linux | mingw | nacl)
+darwin | freebsd | linux | windows | nacl)
 	;;
 *)
-	echo '$GOOS is set to <'$GOOS'>, must be darwin, freebsd, linux, mingw, or nacl' 1>&2
+	echo '$GOOS is set to <'$GOOS'>, must be darwin, freebsd, linux, windows, or nacl' 1>&2
 	exit 1
 esac
 
diff --git a/src/lib9/Makefile b/src/lib9/Makefile
index 3061cfdbb43..ccaf41a0fea 100644
--- a/src/lib9/Makefile
+++ b/src/lib9/Makefile
@@ -81,7 +81,7 @@ LIB9OFILES=\
 	time.$O\
 	tokenize.$O\
 
-ifeq ($(GOOS),mingw)
+ifeq ($(GOOS),windows)
 LIB9OFILES+=\
 	win32.$O\
 
diff --git a/src/libcgo/Makefile b/src/libcgo/Makefile
index deb6b48a341..0d65af70c7d 100755
--- a/src/libcgo/Makefile
+++ b/src/libcgo/Makefile
@@ -23,7 +23,7 @@ CFLAGS_amd64=-m64
 LDFLAGS_linux=-shared -lpthread -lm
 LDFLAGS_darwin=-dynamiclib -Wl,-undefined,dynamic_lookup /usr/lib/libpthread.dylib
 LDFLAGS_freebsd=-pthread -shared -lm
-LDFLAGS_mingw=-shared -lm -mthreads
+LDFLAGS_windows=-shared -lm -mthreads
 
 %.o: %.c
 	gcc $(CFLAGS_$(GOARCH)) -O2 -fPIC -o $@ -c $*.c
diff --git a/src/libcgo/mingw_386.c b/src/libcgo/windows_386.c
similarity index 100%
rename from src/libcgo/mingw_386.c
rename to src/libcgo/windows_386.c
diff --git a/src/libcgo/mingw_amd64.c b/src/libcgo/windows_amd64.c
similarity index 100%
rename from src/libcgo/mingw_amd64.c
rename to src/libcgo/windows_amd64.c
diff --git a/src/libmach/Makefile b/src/libmach/Makefile
index 69d52c288cb..900d2786176 100644
--- a/src/libmach/Makefile
+++ b/src/libmach/Makefile
@@ -48,7 +48,7 @@ OFILES=\
 	6obj.$O\
 	8obj.$O\
 
-ifneq ($(GOOS),mingw)
+ifneq ($(GOOS),windows)
 OFILES+=\
 	$(shell uname | tr A-Z a-z).$O\
 
diff --git a/src/pkg/debug/proc/proc_mingw.go b/src/pkg/debug/proc/proc_windows.go
similarity index 75%
rename from src/pkg/debug/proc/proc_mingw.go
rename to src/pkg/debug/proc/proc_windows.go
index c3e07688ba6..dc22faef81b 100644
--- a/src/pkg/debug/proc/proc_mingw.go
+++ b/src/pkg/debug/proc/proc_windows.go
@@ -6,10 +6,10 @@ package proc
 
 import "os"
 
-// Process tracing is not supported on MinGW yet.
+// Process tracing is not supported on windows yet.
 
 func Attach(pid int) (Process, os.Error) {
-	return nil, os.NewError("debug/proc not implemented on MinGW")
+	return nil, os.NewError("debug/proc not implemented on windows")
 }
 
 func ForkExec(argv0 string, argv []string, envv []string, dir string, fd []*os.File) (Process, os.Error) {
diff --git a/src/pkg/debug/proc/regs_mingw_386.go b/src/pkg/debug/proc/regs_windows_386.go
similarity index 100%
rename from src/pkg/debug/proc/regs_mingw_386.go
rename to src/pkg/debug/proc/regs_windows_386.go
diff --git a/src/pkg/debug/proc/regs_mingw_amd64.go b/src/pkg/debug/proc/regs_windows_amd64.go
similarity index 100%
rename from src/pkg/debug/proc/regs_mingw_amd64.go
rename to src/pkg/debug/proc/regs_windows_amd64.go
diff --git a/src/pkg/os/Makefile b/src/pkg/os/Makefile
index ebb1665d425..71de9495147 100644
--- a/src/pkg/os/Makefile
+++ b/src/pkg/os/Makefile
@@ -34,9 +34,9 @@ GOFILES_nacl=\
 	file_unix.go\
 	sys_nacl.go\
 
-GOFILES_mingw=\
-	file_mingw.go\
-	sys_mingw.go\
+GOFILES_windows=\
+	file_windows.go\
+	sys_windows.go\
 
 GOFILES+=$(GOFILES_$(GOOS))
 
diff --git a/src/pkg/os/dir_mingw.go b/src/pkg/os/dir_windows.go
similarity index 100%
rename from src/pkg/os/dir_mingw.go
rename to src/pkg/os/dir_windows.go
diff --git a/src/pkg/os/file_mingw.go b/src/pkg/os/file_windows.go
similarity index 100%
rename from src/pkg/os/file_mingw.go
rename to src/pkg/os/file_windows.go
diff --git a/src/pkg/os/stat_mingw.go b/src/pkg/os/stat_windows.go
similarity index 100%
rename from src/pkg/os/stat_mingw.go
rename to src/pkg/os/stat_windows.go
diff --git a/src/pkg/os/sys_mingw.go b/src/pkg/os/sys_windows.go
similarity index 100%
rename from src/pkg/os/sys_mingw.go
rename to src/pkg/os/sys_windows.go
diff --git a/src/pkg/runtime/Makefile b/src/pkg/runtime/Makefile
index 6b3ab21e354..881f15a1a1a 100644
--- a/src/pkg/runtime/Makefile
+++ b/src/pkg/runtime/Makefile
@@ -17,7 +17,7 @@ CFLAGS_64=-D_64BIT
 # TODO(kaib): fix register allocation to honor extern register so we
 # can enable optimizations again.
 CFLAGS_arm=-N
-CFLAGS_mingw=-D__MINGW__
+CFLAGS_windows=-D__WINDOWS__
 CFLAGS=-I$(GOOS) -I$(GOARCH) -I$(GOOS)/$(GOARCH) -wF $(CFLAGS_$(SIZE)) $(CFLAGS_$(GOARCH)) $(CFLAGS_$(GOOS))
 
 GOFILES=\
@@ -29,7 +29,7 @@ GOFILES=\
 GOFILES_pchw=\
 	pchw/io.go\
 
-OFILES_mingw=\
+OFILES_windows=\
 	syscall.$O\
 
 # 386-specific object files
diff --git a/src/pkg/runtime/mkasmh.sh b/src/pkg/runtime/mkasmh.sh
index fdd26684064..aae773cfee1 100755
--- a/src/pkg/runtime/mkasmh.sh
+++ b/src/pkg/runtime/mkasmh.sh
@@ -19,7 +19,7 @@ case "$GOARCH" in
 	#	../../libcgo/linux_386.c:/^start
 	#	../../libcgo/darwin_386.c:/^start
 	case "$GOOS" in
-	mingw)
+	windows)
 		echo '#define	get_tls(r)	MOVL 0x2c(FS), r'
 		echo '#define	g(r)	0(r)'
 		echo '#define	m(r)	4(r)'
diff --git a/src/pkg/runtime/runtime.h b/src/pkg/runtime/runtime.h
index ca957f177d9..ff4f463b37c 100644
--- a/src/pkg/runtime/runtime.h
+++ b/src/pkg/runtime/runtime.h
@@ -117,7 +117,7 @@ enum
 struct	Lock
 {
 	uint32	key;
-#ifdef __MINGW__
+#ifdef __WINDOWS__
 	void*	event;
 #else
 	uint32	sema;	// for OS X
@@ -231,7 +231,7 @@ struct	M
 	MCache	*mcache;
 	G*	lockedg;
 	uint64 freg[8];	// Floating point register storage used by ARM software fp routines
-#ifdef __MINGW__
+#ifdef __WINDOWS__
 	void*	return_address;	// saved return address and stack
 	void*	stack_pointer;	// pointer for Windows stdcall
 	void*	os_stack_pointer;
diff --git a/src/pkg/runtime/symtab.c b/src/pkg/runtime/symtab.c
index 4707b1537b9..0284c9f0198 100644
--- a/src/pkg/runtime/symtab.c
+++ b/src/pkg/runtime/symtab.c
@@ -39,7 +39,7 @@ walksymtab(void (*fn)(Sym*))
 	if(symdat == nil)
 		return;
 
-#ifdef __MINGW__
+#ifdef __WINDOWS__
 	v = get_symdat_addr();
 	p = (byte*)v+8;
 #else
@@ -256,7 +256,7 @@ splitpcln(void)
 		return;
 
 	// pc/ln table bounds
-#ifdef __MINGW__
+#ifdef __WINDOWS__
 	v = get_symdat_addr();
 	p = (byte*)v+8;
 #else
diff --git a/src/pkg/runtime/mingw/386/defs.h b/src/pkg/runtime/windows/386/defs.h
similarity index 100%
rename from src/pkg/runtime/mingw/386/defs.h
rename to src/pkg/runtime/windows/386/defs.h
diff --git a/src/pkg/runtime/mingw/386/rt0.s b/src/pkg/runtime/windows/386/rt0.s
similarity index 85%
rename from src/pkg/runtime/mingw/386/rt0.s
rename to src/pkg/runtime/windows/386/rt0.s
index efd8ce3e684..4e685041663 100644
--- a/src/pkg/runtime/mingw/386/rt0.s
+++ b/src/pkg/runtime/windows/386/rt0.s
@@ -2,5 +2,5 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-TEXT	_rt0_386_mingw(SB),7,$0
+TEXT	_rt0_386_windows(SB),7,$0
 	JMP	_rt0_386(SB)
diff --git a/src/pkg/runtime/mingw/386/signal.c b/src/pkg/runtime/windows/386/signal.c
similarity index 100%
rename from src/pkg/runtime/mingw/386/signal.c
rename to src/pkg/runtime/windows/386/signal.c
diff --git a/src/pkg/runtime/mingw/386/sys.s b/src/pkg/runtime/windows/386/sys.s
similarity index 100%
rename from src/pkg/runtime/mingw/386/sys.s
rename to src/pkg/runtime/windows/386/sys.s
diff --git a/src/pkg/runtime/mingw/defs.c b/src/pkg/runtime/windows/defs.c
similarity index 100%
rename from src/pkg/runtime/mingw/defs.c
rename to src/pkg/runtime/windows/defs.c
diff --git a/src/pkg/runtime/mingw/mem.c b/src/pkg/runtime/windows/mem.c
similarity index 100%
rename from src/pkg/runtime/mingw/mem.c
rename to src/pkg/runtime/windows/mem.c
diff --git a/src/pkg/runtime/mingw/os.h b/src/pkg/runtime/windows/os.h
similarity index 91%
rename from src/pkg/runtime/mingw/os.h
rename to src/pkg/runtime/windows/os.h
index 0de38852439..98876c888e0 100644
--- a/src/pkg/runtime/mingw/os.h
+++ b/src/pkg/runtime/windows/os.h
@@ -16,8 +16,8 @@ extern void *LoadLibraryEx;
 extern void *GetProcAddress;
 extern void *GetLastError;
 
-#define goargs mingw_goargs
-void mingw_goargs(void);
+#define goargs windows_goargs
+void windows_goargs(void);
 
 // Get start address of symbol data in memory.
 void *get_symdat_addr(void);
diff --git a/src/pkg/runtime/mingw/syscall.goc b/src/pkg/runtime/windows/syscall.goc
similarity index 100%
rename from src/pkg/runtime/mingw/syscall.goc
rename to src/pkg/runtime/windows/syscall.goc
diff --git a/src/pkg/runtime/mingw/thread.c b/src/pkg/runtime/windows/thread.c
similarity index 99%
rename from src/pkg/runtime/mingw/thread.c
rename to src/pkg/runtime/windows/thread.c
index 9a0bf2a8a64..b5f8cc0330a 100644
--- a/src/pkg/runtime/mingw/thread.c
+++ b/src/pkg/runtime/windows/thread.c
@@ -80,7 +80,7 @@ get_proc_addr(void *library, void *name)
 }
 
 void
-mingw_goargs(void)
+windows_goargs(void)
 {
 	extern Slice os·Args;
 	extern Slice os·Envs;
diff --git a/src/pkg/syscall/asm_mingw_386.s b/src/pkg/syscall/asm_windows_386.s
similarity index 66%
rename from src/pkg/syscall/asm_mingw_386.s
rename to src/pkg/syscall/asm_windows_386.s
index c1bd3cc9ed7..3d9f6fc9434 100644
--- a/src/pkg/syscall/asm_mingw_386.s
+++ b/src/pkg/syscall/asm_windows_386.s
@@ -3,5 +3,5 @@
 // license that can be found in the LICENSE file.
 
 //
-// System calls for 386, Windows are implemented in ../runtime/mingw/syscall.cgo
+// System calls for 386, Windows are implemented in ../runtime/windows/syscall.cgo
 //
diff --git a/src/pkg/syscall/mkall.sh b/src/pkg/syscall/mkall.sh
index 714a47ead2e..06c18987200 100755
--- a/src/pkg/syscall/mkall.sh
+++ b/src/pkg/syscall/mkall.sh
@@ -150,8 +150,8 @@ linux_arm)
 	mktypes="godefs -gsyscall -carm-gcc"
 	mkerrors="./mkerrors.sh"
 	;;
-mingw_386)
-	mksyscall="./mksyscall_mingw.sh -l32"
+windows_386)
+	mksyscall="./mksyscall_windows.sh -l32"
 	mksysnum=
 	mktypes=
 	mkerrors=
diff --git a/src/pkg/syscall/mksyscall_mingw.sh b/src/pkg/syscall/mksyscall_windows.sh
similarity index 97%
rename from src/pkg/syscall/mksyscall_mingw.sh
rename to src/pkg/syscall/mksyscall_windows.sh
index 0daceac4ec4..77320153957 100755
--- a/src/pkg/syscall/mksyscall_mingw.sh
+++ b/src/pkg/syscall/mksyscall_windows.sh
@@ -23,7 +23,7 @@
 #	  //sys LoadLibrary(libname string) (handle uint32, errno int) [failretval=-1] = LoadLibraryA
 #	  and is 0 by default.
 
-$cmdline = "mksyscall_mingw.sh " . join(' ', @ARGV);
+$cmdline = "mksyscall_windows.sh " . join(' ', @ARGV);
 $errors = 0;
 $_32bit = "";
 
@@ -36,7 +36,7 @@ if($ARGV[0] eq "-b32") {
 }
 
 if($ARGV[0] =~ /^-/) {
-	print STDERR "usage: mksyscall_mingw.sh [-b32 | -l32] [file ...]\n";
+	print STDERR "usage: mksyscall_windows.sh [-b32 | -l32] [file ...]\n";
 	exit 1;
 }
 
diff --git a/src/pkg/syscall/syscall_mingw.go b/src/pkg/syscall/syscall_windows.go
similarity index 96%
rename from src/pkg/syscall/syscall_mingw.go
rename to src/pkg/syscall/syscall_windows.go
index be09480dbdb..ec889f9e607 100644
--- a/src/pkg/syscall/syscall_mingw.go
+++ b/src/pkg/syscall/syscall_windows.go
@@ -11,7 +11,7 @@ import (
 	"utf16"
 )
 
-const OS = "mingw"
+const OS = "windows"
 
 /*
 
@@ -72,7 +72,7 @@ func StringToUTF16Ptr(s string) *uint16 { return &StringToUTF16(s)[0] }
 
 // dll helpers
 
-// implemented in ../pkg/runtime/mingw/syscall.cgo
+// implemented in ../pkg/runtime/windows/syscall.cgo
 func Syscall9(trap, a1, a2, a3, a4, a5, a6, a7, a8, a9 uintptr) (r1, r2, lasterr uintptr)
 func loadlibraryex(filename uintptr) (handle uint32)
 func getprocaddress(handle uint32, procname uintptr) (proc uintptr)
@@ -134,7 +134,7 @@ func Sleep(nsec int64) (errno int) {
 }
 
 func Errstr(errno int) string {
-	if errno == EMINGW {
+	if errno == EWINDOWS {
 		return "not supported by windows"
 	}
 	b := make([]uint16, 300)
@@ -381,32 +381,32 @@ const (
 func Getpid() (pid int)   { return -1 }
 func Getppid() (ppid int) { return -1 }
 
-func Fchdir(fd int) (errno int)                           { return EMINGW }
-func Link(oldpath, newpath string) (errno int)            { return EMINGW }
-func Symlink(path, link string) (errno int)               { return EMINGW }
-func Readlink(path string, buf []byte) (n int, errno int) { return 0, EMINGW }
-func Chmod(path string, mode int) (errno int)             { return EMINGW }
-func Fchmod(fd int, mode int) (errno int)                 { return EMINGW }
-func Chown(path string, uid int, gid int) (errno int)     { return EMINGW }
-func Lchown(path string, uid int, gid int) (errno int)    { return EMINGW }
-func Fchown(fd int, uid int, gid int) (errno int)         { return EMINGW }
+func Fchdir(fd int) (errno int)                           { return EWINDOWS }
+func Link(oldpath, newpath string) (errno int)            { return EWINDOWS }
+func Symlink(path, link string) (errno int)               { return EWINDOWS }
+func Readlink(path string, buf []byte) (n int, errno int) { return 0, EWINDOWS }
+func Chmod(path string, mode int) (errno int)             { return EWINDOWS }
+func Fchmod(fd int, mode int) (errno int)                 { return EWINDOWS }
+func Chown(path string, uid int, gid int) (errno int)     { return EWINDOWS }
+func Lchown(path string, uid int, gid int) (errno int)    { return EWINDOWS }
+func Fchown(fd int, uid int, gid int) (errno int)         { return EWINDOWS }
 
 func Getuid() (uid int)                  { return -1 }
 func Geteuid() (euid int)                { return -1 }
 func Getgid() (gid int)                  { return -1 }
 func Getegid() (egid int)                { return -1 }
-func Getgroups() (gids []int, errno int) { return nil, EMINGW }
+func Getgroups() (gids []int, errno int) { return nil, EWINDOWS }
 
 // TODO(brainman): fix all this meaningless code, it is here to compile exec.go
 
-func Pipe(p []int) (errno int) { return EMINGW }
+func Pipe(p []int) (errno int) { return EWINDOWS }
 
 func read(fd int, buf *byte, nbuf int) (n int, errno int) {
-	return 0, EMINGW
+	return 0, EWINDOWS
 }
 
 func fcntl(fd, cmd, arg int) (val int, errno int) {
-	return 0, EMINGW
+	return 0, EWINDOWS
 }
 
 const (
@@ -439,7 +439,7 @@ type Rusage struct {
 }
 
 func Wait4(pid int, wstatus *WaitStatus, options int, rusage *Rusage) (wpid int, errno int) {
-	return 0, EMINGW
+	return 0, EWINDOWS
 }
 
 type WaitStatus uint32
diff --git a/src/pkg/syscall/syscall_mingw_386.go b/src/pkg/syscall/syscall_windows_386.go
similarity index 100%
rename from src/pkg/syscall/syscall_mingw_386.go
rename to src/pkg/syscall/syscall_windows_386.go
diff --git a/src/pkg/syscall/zerrors_mingw_386.go b/src/pkg/syscall/zerrors_windows_386.go
similarity index 94%
rename from src/pkg/syscall/zerrors_mingw_386.go
rename to src/pkg/syscall/zerrors_windows_386.go
index 606ccab7bd6..d8b22846c7f 100644
--- a/src/pkg/syscall/zerrors_mingw_386.go
+++ b/src/pkg/syscall/zerrors_windows_386.go
@@ -3,7 +3,7 @@
 
 package syscall
 
-// TODO(brainman): populate errors in zerrors_mingw.go
+// TODO(brainman): populate errors in zerrors_windows.go
 
 const (
 	ERROR_FILE_NOT_FOUND      = 2
@@ -12,8 +12,8 @@ const (
 	ERROR_MOD_NOT_FOUND       = 126
 	ERROR_PROC_NOT_FOUND      = 127
 	ERROR_DIRECTORY           = 267
-	// TODO(brainman): should use value for EMINGW that does not clashes with anything else
-	EMINGW = 99999 /* otherwise unused */
+	// TODO(brainman): should use value for EWINDOWS that does not clashes with anything else
+	EWINDOWS = 99999 /* otherwise unused */
 )
 
 // TODO(brainman): fix all needed for os
diff --git a/src/pkg/syscall/zsyscall_mingw_386.go b/src/pkg/syscall/zsyscall_windows_386.go
similarity index 100%
rename from src/pkg/syscall/zsyscall_mingw_386.go
rename to src/pkg/syscall/zsyscall_windows_386.go
diff --git a/src/pkg/syscall/zsysnum_mingw_386.go b/src/pkg/syscall/zsysnum_windows_386.go
similarity index 100%
rename from src/pkg/syscall/zsysnum_mingw_386.go
rename to src/pkg/syscall/zsysnum_windows_386.go
diff --git a/src/pkg/syscall/ztypes_mingw_386.go b/src/pkg/syscall/ztypes_windows_386.go
similarity index 98%
rename from src/pkg/syscall/ztypes_mingw_386.go
rename to src/pkg/syscall/ztypes_windows_386.go
index 95ffb4abfef..d6f2d720909 100644
--- a/src/pkg/syscall/ztypes_mingw_386.go
+++ b/src/pkg/syscall/ztypes_windows_386.go
@@ -4,7 +4,7 @@
 
 package syscall
 
-// TODO(brainman): autogenerate types in ztypes_mingw_386.go
+// TODO(brainman): autogenerate types in ztypes_windows_386.go
 
 //import "unsafe"