 Patients with a primary invasive melanoma are recommended to undergo excision of the primary lesion with a wide margin. There is evidence that less radical margins of excision may be just as safe. This is a randomised controlled trial of 1 cm versus 2 cm margin of excision of the primary lesion for adult patients with a primary invasive cutaneous melanomas 1mm thick to determine differences in the rate of local recurrence and melanoma specific survival. A reduction in margins is expected to improve quality of life in patients 