Besides surgical intervention, there are virtually no palliative treatment modalities available for bleeding and/or obstructing colorectal malignancy. The usefulness and safety of laser photocoagulation was prospectively investigated in 63 patients with colorectal cancer. The merits were evaluated in the treatment of obstruction (16 patients), bleeding (32 patients), and combined hemorrhage and obstruction (15 patients). Luminal patency could be restored in 15 (94%), hemostasis was achieved in 28 (88%), and treatment was effective in 13 (87%) patients with bleeding and obstructing tumors. In the 56 evaluable and initially responding patients, no beneficial long-term results were achieved in six patients, as major complications of (re)stenosis, necessitating colostomy, occurred in three, posttreatment hemorrhage with need for blood transfusion in two, and a pararectal abscess formation was seen in one patient. Except probably for this pararectal abscess, there was no treatment-related death. Transient stenosis and laser-induced bleeding, as minor complications present in 12 (19%), responded favorably upon reinstitution of laser photocoagulation. The beneficial effect of laser photocoagulation was, in general, evident after 2 to 3 sessions. Fortysix patients could be discharged from the hospital and their treatment could be continued in the outpatient clinic. Further hospital admission could be avoided in 39. Laser treatment for palliation of obstructing and/or bleeding colorectal cancer proved to be an efficacious, safe, and rapidly effective therapy. Laser photocoagulation can be considered as a valuable alternative to aggressive surgical intervention in the absence of other conservative treatment modalities in palliation.