From the Babylonian period to the twentieth century, strictly observant Jews have depended on a non-Jew, or "shabbes goy" to perform work that was forbidden on the Sabbath. The author traces the role of the "shabbes goy" through the centuries. Katz affords the "shabbes goy" the central role in this fascinating case study on the larger question of the adapatability of halakhah to the ever-changing circumstances of life.