diff --git a/AUTHORS b/AUTHORS
index 6e760ad..d1ac7f3 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -11,6 +11,7 @@ Patches and Suggestions
 
 - Kenneth Reitz
 - Aggelos Orfanakos
+- Jonathan "Duke" Leto
 - Domenico Rotiroti
 - Jason Young
 - Nick Campbell
diff --git a/Readme.md b/Readme.md
index 448eb15..07b1cbf 100644
--- a/Readme.md
+++ b/Readme.md
@@ -67,6 +67,10 @@ Outputs a repo summary:
 	      1	isaacs         
 	      1	Matt Colyer    
 
+This command can also take a commitish, and will print a summary for the range
+of commits included in the commitish:
+
+  $ git summary v42..
 
 ## git-repl
 
diff --git a/bin/git-summary b/bin/git-summary
index 9996b26..d1333c2 100755
--- a/bin/git-summary
+++ b/bin/git-summary
@@ -1,14 +1,18 @@
 #!/bin/sh
 
+COMMITISH=""
+test $# -ne 0 && COMMITISH=$@
 project=${PWD##*/}
-commit_count=`git log --oneline | wc -l | tr -d ' '`
+commit_count=`git log --oneline $COMMITISH | wc -l | tr -d ' '`
 file_count=`git ls-files | wc -l | tr -d ' '`
-authors=`git shortlog -n -s`
+authors=`git shortlog -n -s $COMMITISH`
 
 echo
 echo " project: $project"
 echo " commits: $commit_count"
-echo " files  : $file_count"
+if test "$COMMITISH" = ""; then
+    echo " files  : $file_count"
+fi
 echo " authors: "
 echo "$authors"
-echo
\ No newline at end of file
+echo