diff --git a/README.W32.template b/README.W32.template
index 3ac3354..9a05307 100644
--- a/README.W32.template
+++ b/README.W32.template
@@ -5,16 +5,15 @@
 It builds with the MinGW port of GCC (tested with GCC 3.4.2, 4.8.1,
 and 4.9.3).
 
-It also builds with MSVC 2.x, 4.x, 5.x, 6.x, 2003, and 14 (2015) as
-well as with .NET 7.x and .NET 2003.
+It also builds with MSVC 2.x, 4.x, 5.x, 6.x, 2005, 2008, 2010, 2012,
+2013, and 2015 as well as with .NET 7.x and .NET 2003.
 
-As of version 4.0, a build with Guile is supported (tested with Guile
-2.0.3).  To build with Guile, you will need, in addition to Guile
-itself, its dependency libraries and the pkg-config program.  The
-latter is used to figure out which compilation and link switches and
-libraries need to be mentioned on the compiler command lines to
-correctly link with Guile.  A Windows port of pkg-config can be found
-on ezwinports site:
+Building with Guile is supported (tested with Guile 2.0.3).  To build
+with Guile, you will need, in addition to Guile itself, its dependency
+libraries and the pkg-config program.  The latter is used to figure out
+which compilation and link switches and libraries need to be mentioned
+on the compiler command lines to correctly link with Guile.  A Windows
+port of pkg-config can be found on ezwinports site:
 
   http://sourceforge.net/projects/ezwinports/
 
@@ -56,7 +55,7 @@
  2. Open a W32 command prompt for your installed (MinGW-)GCC, setup a
     correct PATH and other environment variables for it, then execute ...
 
-        build_w32.bat gcc
+        .\build_w32.bat gcc
 
     This produces gnumake.exe in the GccRel directory.
     If you want a version of GNU make built with debugging enabled,
@@ -66,35 +65,44 @@
     gnumake.exe with Guile if it finds it.  If you have Guile
     installed, but want to build Make without Guile support, type
 
-        build_w32.bat --without-guile gcc
+        .\build_w32.bat --without-guile gcc
 
 
-Building with (MSVC++-)cl using build_w32.bat or NMakefile
-----------------------------------------------------------
+Building with (MSVC++-)cl using build_w32.bat
+---------------------------------------------
+
+ 2. Open a command shell, then execute ...
+
+        .\build_w32.bat
+
+    This produces a 64bit Release build of gnumake.exe in .\WinRel, using
+    the compiler found on the %Path%.  If no compiler is found, the batch
+    file will probe your system and choose the newest MSVC version it can
+    find.
+
+    If you want a 32bit version of GNU make, add the --x86 option.
+
+    If you want a Debug build of GNU make, add the --debug option.
+
+    The batch file will probe for Guile installation, and will build
+    gnumake.exe with Guile if it finds it.  If Guile is installed,
+    but you prefer to build GNU make without Guile support, add the
+    --without-guile option.
+
+
+Building with (MSVC++-)cl using NMakefile
+-----------------------------------------
 
  2. Open a W32 command prompt for your installed (MSVC++-)cl, setup a
     correct PATH and other environment variables for it (usually via
-    executing vcvars32.bat or vsvars32.bat from the cl-installation,
-    e.g. "%VS71COMNTOOLS%vsvars32.bat"; or using a corresponding start
-    menue entry from the cl-installation), then execute EITHER ...
-
-        build_w32.bat
-
-    This produces gnumake.exe in the WinRel directory.
-    If you want a version of GNU make built with debugging enabled,
-    add the --debug option.
-
-    ... OR ...
+    executing vcvars32.bat or vsvars32.bat from the cl-installation, or
+    using a corresponding start menu entry from the cl-installation),
+    then execute ...
 
         nmake /f NMakefile
 
     (this produces WinDebug/make.exe and WinRel/make.exe).
 
-    The batch file will probe for Guile installation, and will build
-    gnumake.exe with Guile if it finds it.  If you have Guile
-    installed, but want to build Make without Guile support, type
-
-        build_w32.bat --without-guile
 
 -------------------
 -- Notes/Caveats --
diff --git a/build_w32.bat b/build_w32.bat
index 59e068b..07b422a 100755
--- a/build_w32.bat
+++ b/build_w32.bat
@@ -15,6 +15,7 @@
 rem You should have received a copy of the GNU General Public License along
 rem with this program.  If not, see <http://www.gnu.org/licenses/>.
 
+setlocal
 call :Reset
 
 if "%1" == "-h" goto Usage
@@ -22,13 +23,17 @@
 
 set MAKE=gnumake
 set GUILE=Y
-set COMPILER=msvc
+set COMPILER=cl.exe
+set ARCH=x64
+set DEBUG=N
 
 :ParseSW
 if "%1" == "--debug" goto SetDebug
 if "%1" == "--without-guile" goto NoGuile
+if "%1" == "--x86" goto Set32Bit
 if "%1" == "gcc" goto SetCC
 if "%1" == "" goto DoneSW
+goto Usage
 
 :SetDebug
 set DEBUG=Y
@@ -41,6 +46,11 @@
 shift
 goto ParseSW
 
+:Set32Bit
+set ARCH=x86
+shift
+goto ParseSW
+
 :SetCC
 set COMPILER=gcc
 echo Building with GCC
@@ -50,11 +60,65 @@
 rem Build with Guile is supported only on NT and later versions
 :DoneSW
 echo.
-echo Creating GNU Make for Windows 9X/NT/2K/XP/Vista/7/8
+echo Creating GNU Make for Windows 9X/NT/2K/XP/Vista/7/8/10
 if "%DEBUG%" == "Y" echo Building without compiler optimizations
 
 if "%COMPILER%" == "gcc" goto GccBuild
 
+rem Make sure we can find a compiler
+%COMPILER% >nul 2>&1
+if not ERRORLEVEL 1 goto FoundMSVC
+
+set "VSVARS=%VS140COMNTOOLS%\..\..\VC\vcvarsall.bat"
+call :CheckMSVC
+if not ERRORLEVEL 1 goto FoundMSVC
+
+set "VSVARS=%VS120COMNTOOLS%\..\..\VC\vcvarsall.bat"
+call :CheckMSVC
+if not ERRORLEVEL 1 goto FoundMSVC
+
+set "VSVARS=%VS110COMNTOOLS%\..\..\VC\vcvarsall.bat"
+call :CheckMSVC
+if not ERRORLEVEL 1 goto FoundMSVC
+
+set "VSVARS=%VS100COMNTOOLS%\..\..\VC\vcvarsall.bat"
+call :CheckMSVC
+if not ERRORLEVEL 1 goto FoundMSVC
+
+set "VSVARS=%VS90COMNTOOLS%\..\..\VC\vcvarsall.bat"
+call :CheckMSVC
+if not ERRORLEVEL 1 goto FoundMSVC
+
+set "VSVARS=%VS80COMNTOOLS%\..\..\VC\vcvarsall.bat"
+call :CheckMSVC
+if not ERRORLEVEL 1 goto FoundMSVC
+
+set "VSVARS=%VS71COMNTOOLS%\..\..\VC\vcvarsall.bat"
+call :CheckMSVC
+if not ERRORLEVEL 1 goto FoundMSVC
+
+set "VSVARS=%VS70COMNTOOLS%\..\..\VC\vcvarsall.bat"
+call :CheckMSVC
+if not ERRORLEVEL 1 goto FoundMSVC
+
+set "VSVARS=%V6TOOLS%\VC98\Bin\vcvars32.bat"
+call :CheckMSVC
+if not ERRORLEVEL 1 goto FoundMSVC
+
+set "VSVARS=%V6TOOLS%\VC97\Bin\vcvars32.bat"
+call :CheckMSVC
+if not ERRORLEVEL 1 goto FoundMSVC
+
+set "VSVARS=%V5TOOLS%\VC\Bin\vcvars32.bat"
+call :CheckMSVC
+if not ERRORLEVEL 1 goto FoundMSVC
+
+rem We did not find anything--fail
+echo No MSVC compiler available.
+echo Please run vcvarsall.bat and/or configure your Path.
+exit /b 1
+
+:FoundMSVC
 set OUTDIR=.\WinRel
 set "OPTS=/O2 /D NDEBUG"
 set LINKOPTS=
@@ -149,7 +213,7 @@
 
 :: MSVC Compile
 echo on
-cl.exe /nologo /MT /W4 /EHsc %OPTS% /I %OUTDIR% /I . /I glob /I w32/include /D WINDOWS32 /D WIN32 /D _CONSOLE /D HAVE_CONFIG_H /FR%OUTDIR% /Fp%OUTDIR%\%MAKE%.pch /Fo%OUTDIR%\%1.obj /Fd%OUTDIR%\%MAKE%.pdb %EXTRAS% /c %1.c
+%COMPILER% /nologo /MT /W4 /EHsc %OPTS% /I %OUTDIR% /I . /I glob /I w32/include /D WINDOWS32 /D WIN32 /D _CONSOLE /D HAVE_CONFIG_H /FR%OUTDIR% /Fp%OUTDIR%\%MAKE%.pch /Fo%OUTDIR%\%1.obj /Fd%OUTDIR%\%MAKE%.pdb %EXTRAS% /c %1.c
 @echo off
 echo %OUTDIR%\%1.obj >>%OUTDIR%\link.sc
 goto :EOF
@@ -226,16 +290,25 @@
 set "GUILECFLAGS=%GUILECFLAGS% -DHAVE_GUILE"
 goto :EOF
 
+:CheckMSVC
+if not exist "%VSVARS%" exit /b 1
+call "%VSVARS%" %ARCH%
+if ERRORLEVEL 1 exit /b 1
+%COMPILER% >nul 2>&1
+if ERRORLEVEL 1 exit /b 1
+goto :EOF
+
 :Usage
 echo Usage: %0 [options] [gcc]
 echo Options:
-echo.  --debug           For GCC only, make a debug build
-echo.                    (MSVC build always makes both debug and release)
 echo.  --without-guile   Do not compile Guile support even if found
+echo.  --debug           Make a Debug build--default is Release
+echo.  --x86             Make a 32bit binary--default is 64bit
 echo.  --help            Display these instructions and exit
 goto :EOF
 
 :Reset
+set ARCH=
 set COMPILER=
 set DEBUG=
 set GUILE=
@@ -247,4 +320,5 @@
 set OPTS=
 set OUTDIR=
 set PKGMSC=
+set VSVARS=
 goto :EOF