The hypnotic efficacy and the effect on the condition after morning awakening of midazolam 15 mg and of triazolam 0.5 mg were studied in a multicentre, double-blind cross-over study in 198 out-patients with sleeping difficulties of various origin. The subjects received each drug for two consecutive nights, and completed a questionnaire each day on awakening. Both midazolam and triazolam significantly shortened the sleep-onset latency, reduced the number of awakenings, and increased the total sleep time. The state on awakening was also significantly improved after both compounds for several self-rated items. There was a difference only with regard to the patients' feeling of being under drug influence, which was reported as being significantly more marked after triazolam. In conclusion, both compounds were effective and well tolerated in the doses used, only a few side-effects being reported.