Since ancient times, larval therapy has been reputed to help wound healing. Its use has recently been rediscovered and it is now enjoying increasing interest in clinical practice, as well as in research. We have investigated the effects of larval therapy on wounds in an open study of 74 patients with necrotic or sloughy chronic ulcers of different aetiologies. We found larval therapy to effectively debride 86% of the necrotic ulcers, and a single application was clinically beneficial in two-thirds of the patients. Failure to debride was mostly attributable to larval death. No ulcer type was shown to be more suited to larval therapy than others; however, there was an excellent response in all 29 patients with diabetes. Larval therapy was also noted to reduce odour in 58% of the 31 foul-smelling ulcers of mixed aetiology. No serious side-effects were observed. One-quarter of the study group experienced less pain during treatment, while 41% felt no difference in pain, and, although 34% noted an increase in pain, most of these patients wanted to continue the treatment because of subjective and objective visual improvement in wound debridement. In conclusion, we found larval therapy to be effective for debriding ulcers, easy to use and well accepted by the patients.