A study of labor induction in 325 patients is reported. Group I (77 patients with Bioshop's scores 0-6) and 2 (69 patients with Bishop's scores 7-12) were given 0.5 mg prostaglandin E2 every half hour (maximum 5 mg per day). Group 3 (87 patients with Bishop's scores 0-6) was givne 50 International units of buccal desaminooxytocin every half hour (maximum 500 International units per day). In Group 4 (92 patients with Bishop's scores 7-12), labor was induced by primary amniotomy and automatic oxytocin infusion by the Cardiff method. In groups 1, 2 and 3, 45 per cent, 74 per cent and 41 per cent delivered within 48 hours, while 100 per cent in group 4 delivered within 24 hours. No differences were found in either the frequency of cesarean section or the incidence of low Apgar scores. A higher, but not statistically significant frequency of vacuum extraction was found in the Cardiff group (25 per cent) than in the tablet-induced groups (15 per cent). There was, however, a significantly higheroccurrence of alterations in fetal heart rate which led to instrumental intervention to hasten delivery in the Cardiff group compared to the tablet-induced patients.