In a randomized study, Nd-YAG laser therapy by the endoscopic contact low-power method was compared with the non-contact high-power method for its palliative action on colorectal carcinoma. With the contact technique, more therapy sessions were required to achieve good recanalization of the bowel than with non-contact therapy (5.0±1.9 sessionsversus 3.0±1.5 sessions;P<0.001), although the total energy applied to the tumour was much lower (5893±2310Jversus 16805±14107J;P=0.05). Contact endoscopic laser therapy (ELT) was better tolerated by the patients than non-contact ELT was especially suitable for lesions that are difficult to treat from a distance. Other advantages of contact ELT are no smoke generation and no risk of damage to endoscopes. Disadvantages of contact ELT are the lack of visual control over therapy, possible damage to healthy tissue, adhesion of the contact sapphire and a high cost. Although contact ELT is more time-consuming and costly than non-contact ELT, both techniques are effective and safe. There seems to be no reason, therefore, to prefer to prefer contact ELT to non-contact therapy: the two techniques could indeed, be complementary.