There is evidence that the solitary rectal ulcer syndrome is associated with rectal prolapse either overt or internal. The anterior rectal wall is affected in most cases and a modified abdominal rectopexy has been used with the aim of supporting both the anterior and posterior aspects of the rectum. Fourteen patients aged 19-70 years (mean 34.2 years) in whom conservative treatment has failed, have been treated by anteroposterior rectopexy. Tenesmus, bleeding and the passage of mucus have been abolished or greatly improved in 12, 14 and 13 patients respectively. The number of attempts to defaecate per 24 h has fallen from 8.7 +/- 1.4(s.e.m.) pre-operatively to 3.4 +/- 1.0(s.e.m.) postoperatively (P less than 0.05) and the time spent in the lavatory has been reduced from 146 +/- 18(s.e.m.) min to 15 +/- 3(s.e.m.) min. Two patients have developed severe constipation postoperatively and two others have had persistent or recurrent tenesmus. Combined anteroposterior rectopexy has improved 12 out of 14 patients with the solitary ulcer syndrome without external rectal prolapse when assessed at 2-48 months postoperatively.