diff --git a/Documentation/git-mergetool.txt b/Documentation/git-mergetool.txt
index 5edac4d267..ff9700d17a 100644
--- a/Documentation/git-mergetool.txt
+++ b/Documentation/git-mergetool.txt
@@ -27,7 +27,7 @@ OPTIONS
 	Use the merge resolution program specified by <tool>.
 	Valid merge tools are:
 	kdiff3, tkdiff, meld, xxdiff, emerge, vimdiff, gvimdiff, ecmerge,
-	tortoisemerge and opendiff
+	diffuse, 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 8c10f66702..4832bc75e2 100644
--- a/Documentation/merge-config.txt
+++ b/Documentation/merge-config.txt
@@ -23,7 +23,7 @@ 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",
-	"ecmerge", tortoisemerge and
+	"diffuse", "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/completion/git-completion.bash b/contrib/completion/git-completion.bash
index d3d8203171..e099ed48ff 100755
--- a/contrib/completion/git-completion.bash
+++ b/contrib/completion/git-completion.bash
@@ -1174,7 +1174,8 @@ _git_mergetool ()
 	--tool=*)
 		__gitcomp "
 			kdiff3 tkdiff meld xxdiff emerge
-			vimdiff gvimdiff ecmerge opendiff
+			vimdiff gvimdiff ecmerge diffuse
+			opendiff
 			" "" "${cur##--tool=}"
 		return
 		;;
diff --git a/contrib/difftool/git-difftool-helper b/contrib/difftool/git-difftool-helper
index e74a2747b6..4b0daec5a7 100755
--- a/contrib/difftool/git-difftool-helper
+++ b/contrib/difftool/git-difftool-helper
@@ -1,7 +1,5 @@
 #!/bin/sh
 # git-difftool-helper is a GIT_EXTERNAL_DIFF-compatible diff tool launcher.
-# It supports kdiff3, kompare, tkdiff, xxdiff, meld, opendiff,
-# emerge, ecmerge, vimdiff, gvimdiff, and custom user-configurable tools.
 # This script is typically launched by using the 'git difftool'
 # convenience command.
 #
@@ -55,6 +53,10 @@ launch_merge_tool () {
 		"$merge_tool_path" "$LOCAL" "$REMOTE"
 		;;
 
+	diffuse)
+		"$merge_tool_path" "$LOCAL" "$REMOTE" | cat
+		;;
+
 	vimdiff)
 		"$merge_tool_path" -d -c "wincmd l" "$LOCAL" "$REMOTE"
 		;;
@@ -164,9 +166,9 @@ if test -z "$merge_tool"; then
 	if test -n "$DISPLAY"; then
 		# If gnome then prefer meld, otherwise, prefer kdiff3 or kompare
 		if test -n "$GNOME_DESKTOP_SESSION_ID" ; then
-			merge_tool_candidates="meld kdiff3 kompare tkdiff xxdiff gvimdiff"
+			merge_tool_candidates="meld kdiff3 kompare tkdiff xxdiff gvimdiff diffuse"
 		else
-			merge_tool_candidates="kdiff3 kompare tkdiff xxdiff meld gvimdiff"
+			merge_tool_candidates="kdiff3 kompare tkdiff xxdiff meld gvimdiff diffuse"
 		fi
 	fi
 	if echo "${VISUAL:-$EDITOR}" | grep 'emacs' > /dev/null 2>&1; then
diff --git a/contrib/difftool/git-difftool.txt b/contrib/difftool/git-difftool.txt
index a00e9431c5..af68466ebc 100644
--- a/contrib/difftool/git-difftool.txt
+++ b/contrib/difftool/git-difftool.txt
@@ -25,8 +25,8 @@ OPTIONS
 --tool=<tool>::
 	Use the diff tool specified by <tool>.
 	Valid merge tools are:
-	kdiff3, kompare, tkdiff, meld, xxdiff, emerge,
-	vimdiff, gvimdiff, ecmerge, and opendiff
+	kdiff3, kompare, tkdiff, meld, xxdiff, emerge, vimdiff, gvimdiff,
+	ecmerge, diffuse and opendiff
 +
 If a diff tool is not specified, 'git-difftool'
 will use the configuration variable `diff.tool`.  If the
diff --git a/git-mergetool.sh b/git-mergetool.sh
index be9717a2f1..b4d2432f02 100755
--- a/git-mergetool.sh
+++ b/git-mergetool.sh
@@ -414,9 +414,9 @@ fi
 if test -z "$merge_tool" ; then
     if test -n "$DISPLAY"; then
         if test -n "$GNOME_DESKTOP_SESSION_ID" ; then
-            merge_tool_candidates="meld kdiff3 tkdiff xxdiff tortoisemerge gvimdiff"
+            merge_tool_candidates="meld kdiff3 tkdiff xxdiff tortoisemerge gvimdiff diffuse"
         else
-            merge_tool_candidates="kdiff3 tkdiff xxdiff meld tortoisemerge gvimdiff"
+            merge_tool_candidates="kdiff3 tkdiff xxdiff meld tortoisemerge gvimdiff diffuse"
         fi
     fi
     if echo "${VISUAL:-$EDITOR}" | grep 'emacs' > /dev/null 2>&1; then