In the ``Beyond Museum Walls'' series, the past and present uses—worldwide—of spirit, carnival, theatrical, portrait, and occupational masks. Nearly every mask mentioned is shown in a photo (usually in color), making the few exceptions (e.g., ancient Greek theater masks) rather glaring. Gelber considers masks not as artworks but as objects with a social purpose—an interesting, useful approach—but illustrating the masks in the context of use means that there are few close-ups. The text is concise and well- organized (though a pronunciation guide would have been helpful); the quality of the photos varies. Bibliography; index. (Nonfiction. 9-12)