The purpose of this paper is to demonstrate the surgical feasibility of en bloc excision of certain tumors of the ciliary body and iris and to suggest that in selected cases this method of treatment should be added to the armamentarium of management. Since 1950 six malignant melanomas of the iris and ciliary body have been excised by ophthalmic surgeons on the Stanford staff, in which the iris and anterior portions of the ciliary body have been removed in one piece. The clinical experience gained from these cases, together with the histologic study of the tissues involved, has led to a better understanding of the surgical pathology of this region. Each surgeon has profited by the experience of his predecessor and has contributed to the evolution of the surgical technique. During this same period of time similar techniques have been developed by various surgeons throughout the world, and it is