A retrospective review has been performed to assess the outcome and toxicity of post-operative adjuvant therapy of 25 Gy/5 fractions/1 week following resection of stage II and III rectal cancer. Forty patients were treated between August 1992 and May 1995. The ages ranged from 42 to 79 (median 63); 32 were male (80%). At last follow up 32 were alive with 0.9 to 11.3 years of follow-up (median 6.6 years). The 5-year actuarial survival was 76% (95% CI: 62-91%). The local relapse free rate was 73% (95% CI: 58-88). Seven patients experienced grade 3 or 4 early toxicity. Three patients had grade 2 or 3 late toxicity. Although treatment was well tolerated, the local relapse rate observed was high. In view of the changes in surgical and pathological techniques in the last decade, further studies are required to determine the merits or otherwise of postoperative Short Course Adjuvant Radiation.