Between 1986 and 1992, 265 men of mean age 51 (range 16-75) years with a primary inguinal hernia were randomized to undergo surgery by staff surgeon or surgical resident and further randomized to receive a modified Bassini operation (transversalis fascia not divided but included in the repair) or Shouldice procedure. The follow-up rate was 92.1 per cent with a mean follow-up of 3.3 years. Recurrence developed in 12 of 125 patients with a Bassini procedure and two of 119 after a Shouldice repair (9.6 versus 1.7 per cent, P = 0.006). The recurrence rate was no different for staff surgeons and trainees (5.9 versus 5.6 per cent, P not significant). Multivariate analysis identified the presence of a direct hernia (P = 0.003) as the additional main factor for the development of recurrence.