Klezmer music has experienced changing musical content and social function since the late 19th. c. In the immigrant period, mostly Eastern European dance tunes were performed by fairly large groups (12-15 performers). As more klezmer music was recorded, it took on the role of a cultural buffer. From the 1940s to the 1960s, however, it shifted back to a live performance context (weddings, bar mitzvahs, etc.) and was associated especially with the Jewish resort milieu of the Catskills. The 1970s revival, related to the general ethnic and folk revival in America, attempted a return to the sound of the earlier recordings. A directory of klezmer performing groups and information resources in the United States is included.