diff --git a/Documentation/git-mergetool.txt b/Documentation/git-mergetool.txt
index 5d3c632872..5edac4d267 100644
--- a/Documentation/git-mergetool.txt
+++ b/Documentation/git-mergetool.txt
@@ -26,7 +26,8 @@ OPTIONS
 --tool=<tool>::
 	Use the merge resolution program specified by <tool>.
 	Valid merge tools are:
-	kdiff3, tkdiff, meld, xxdiff, emerge, vimdiff, gvimdiff, ecmerge, and opendiff
+	kdiff3, tkdiff, meld, xxdiff, emerge, vimdiff, gvimdiff, ecmerge,
+	tortoisemerge and opendiff
 +
 If a merge resolution program is not specified, 'git-mergetool'
 will use the configuration variable `merge.tool`.  If the
diff --git a/Documentation/merge-config.txt b/Documentation/merge-config.txt
index 1ff08ff2cc..8c10f66702 100644
--- a/Documentation/merge-config.txt
+++ b/Documentation/merge-config.txt
@@ -22,7 +22,8 @@ merge.stat::
 merge.tool::
 	Controls which merge resolution program is used by
 	linkgit:git-mergetool[1].  Valid built-in values are: "kdiff3",
-	"tkdiff", "meld", "xxdiff", "emerge", "vimdiff", "gvimdiff", and
+	"tkdiff", "meld", "xxdiff", "emerge", "vimdiff", "gvimdiff",
+	"ecmerge", tortoisemerge and
 	"opendiff".  Any other value is treated is custom merge tool
 	and there must be a corresponding mergetool.<tool>.cmd option.
 
diff --git a/contrib/difftool/git-difftool-helper b/contrib/difftool/git-difftool-helper
index 9c0a13452a..e481913c91 100755
--- a/contrib/difftool/git-difftool-helper
+++ b/contrib/difftool/git-difftool-helper
@@ -86,11 +86,11 @@ launch_merge_tool () {
 		;;
 
 	vimdiff)
-		"$merge_tool_path" -c "wincmd l" "$LOCAL" "$REMOTE"
+		"$merge_tool_path" -d -c "wincmd l" "$LOCAL" "$REMOTE"
 		;;
 
 	gvimdiff)
-		"$merge_tool_path" -c "wincmd l" -f "$LOCAL" "$REMOTE"
+		"$merge_tool_path" -d -c "wincmd l" -f "$LOCAL" "$REMOTE"
 		;;
 
 	xxdiff)
@@ -160,6 +160,12 @@ init_merge_tool_path() {
 	merge_tool_path=$(git config mergetool."$1".path)
 	if test -z "$merge_tool_path"; then
 		case "$1" in
+		vimdiff)
+			merge_tool_path=vim
+			;;
+		gvimdiff)
+			merge_tool_path=gvim
+			;;
 		emerge)
 			merge_tool_path=emacs
 			;;
diff --git a/git-mergetool.sh b/git-mergetool.sh
index 87fa88af55..be9717a2f1 100755
--- a/git-mergetool.sh
+++ b/git-mergetool.sh
@@ -214,12 +214,12 @@ merge_file () {
 	    ;;
 	vimdiff)
 	    touch "$BACKUP"
-	    "$merge_tool_path" -c "wincmd l" "$LOCAL" "$MERGED" "$REMOTE"
+	    "$merge_tool_path" -d -c "wincmd l" "$LOCAL" "$MERGED" "$REMOTE"
 	    check_unchanged
 	    ;;
 	gvimdiff)
 	    touch "$BACKUP"
-	    "$merge_tool_path" -c "wincmd l" -f "$LOCAL" "$MERGED" "$REMOTE"
+	    "$merge_tool_path" -d -c "wincmd l" -f "$LOCAL" "$MERGED" "$REMOTE"
 	    check_unchanged
 	    ;;
 	xxdiff)
@@ -265,6 +265,16 @@ merge_file () {
 	    fi
 	    status=$?
 	    ;;
+	tortoisemerge)
+	    if base_present ; then
+		touch "$BACKUP"
+		"$merge_tool_path" -base:"$BASE" -mine:"$LOCAL" -theirs:"$REMOTE" -merged:"$MERGED"
+		check_unchanged
+	    else
+		echo "TortoiseMerge cannot be used without a base" 1>&2
+		status=1
+	    fi
+	    ;;
 	*)
 	    if test -n "$merge_tool_cmd"; then
 		if test "$merge_tool_trust_exit_code" = "false"; then
@@ -345,7 +355,7 @@ valid_custom_tool()
 
 valid_tool() {
 	case "$1" in
-		kdiff3 | tkdiff | xxdiff | meld | opendiff | emerge | vimdiff | gvimdiff | ecmerge)
+		kdiff3 | tkdiff | xxdiff | meld | opendiff | emerge | vimdiff | gvimdiff | ecmerge | tortoisemerge)
 			;; # happy
 		*)
 			if ! valid_custom_tool "$1"; then
@@ -359,6 +369,12 @@ init_merge_tool_path() {
 	merge_tool_path=`git config mergetool.$1.path`
 	if test -z "$merge_tool_path" ; then
 		case "$1" in
+			vimdiff)
+				merge_tool_path=vim
+				;;
+			gvimdiff)
+				merge_tool_path=gvim
+				;;
 			emerge)
 				merge_tool_path=emacs
 				;;
@@ -398,9 +414,9 @@ fi
 if test -z "$merge_tool" ; then
     if test -n "$DISPLAY"; then
         if test -n "$GNOME_DESKTOP_SESSION_ID" ; then
-            merge_tool_candidates="meld kdiff3 tkdiff xxdiff gvimdiff"
+            merge_tool_candidates="meld kdiff3 tkdiff xxdiff tortoisemerge gvimdiff"
         else
-            merge_tool_candidates="kdiff3 tkdiff xxdiff meld gvimdiff"
+            merge_tool_candidates="kdiff3 tkdiff xxdiff meld tortoisemerge gvimdiff"
         fi
     fi
     if echo "${VISUAL:-$EDITOR}" | grep 'emacs' > /dev/null 2>&1; then