Excellent recommendation, Mark! I use the book.

Since we're sharing other peace songs than the one initially requested, here are a few others we love at my school:
Peace Round by our own Jean Ritchie (kytrad)
Shalom, chaverim-
(sing each as a round, then sing the two together as partner songs- hauntinly beautiful!)
I've got Peace like a river
Rainbow Tribe by Steve Schuch (listen to a clip)

Allison