Tumors and tumor-like lesions of the pigment epithelium of the iris, ciliary body, and retina are discussed with special emphasis on definitions and the various elements of help in the differential diagnosis. One of these lesions, hypertrophy of the retinal pigment epithelium, is classically described as non-progressive. However, we report here 4 cases with documented progression of various forms. The etiology and physiopathologic considerations are discussed. Although most tumors and pseudotumors of the ocular pigment epithelium are benign, malignant forms and various non-malignant, but progressive types can occur.