This study describes how surgery for Crohn colitis developed between 1970 and 1997, towards the end of which period limited resection and medical maintenance treatment was introduced. A cohort of 211 patients with Crohn colitis (115 population-based), of which 84 had a primary colonic resection (42 population-based), was investigated regarding indication for surgery, the time from diagnosis to operation, type of primary colonic resection, risk for permanent stoma and medication over four 7-year periods. Comparison of the periods 1970-90 and 1991-97 revealed that active disease as an indication for surgery decreased from 64% to 25% (P<0.01) while stricture as an indication increased from 9% to 50% (P < 0.001). Median time from diagnosis to operation increased from 3.5 to 11.5 years (P < 0.01). Proctocolectomy or colectomy fell from 68.8% to 10% of the primary resections, whereas segmental resection increased from 31.2% to 90%. At the end of the first 7-year period, 26% had medical maintenance treatment, steroids or azathioprine taken by 7%. Corresponding figures for the last period were 70% and 49%. Patients diagnosed during the last two time-periods had less risk for surgery (P = 0.017), permanent stoma (P < 0.01) and total colectomy (P < 0.01). Findings were similar in the population-based cohort. Current management of Crohn colitis implies a longer period between diagnosis and surgery, a reduced risk for surgery and permanent stoma, and the replacement of total colectomy by segmental resection.