One hundred and seventy-three Jewish women of child-bearing age attending their family doctor were asked about their contraceptive practices and attitudes. Medical means of contraception were used by 42% of the women and coitus interruptus by 44%. Although coitus interruptus is prohibited by Jewish ritual law, its use in fact applies to all age groups of women, irrespective of religiousness or family size. The small group of contraceptive pill users (17%) were younger, had smaller families and expressed a greater readiness to consider abortion in case of accidental pregnancy than the rest of the sample. They were less observant of the religious laws and might be described as ‘modern’ compared with the larger group of ‘traditional’ women. The latter preferred the intrauterine device and had larger families, but would not consider abortion, which is forbidden by Jewish law in most cases. The evidence demonstrated that the mainly traditional patients do not conform to the pattern of behaviour prescribed by their religion as closely as expected. As a result of this survey the authors are actively advocating the intrauterine device as a more effective, acceptable alternative to coitus interruptus.