This paper presents the results of a 20 year survey of ROP among less than or equal to 2000 g BW infants cared for at Pennsylvania Hospital. It relates changes in perinatal care and nutrition, survival rates, and serial serum E levels with incidence and severity of ROP. It includes our protocol for monitoring E nutrition so as to optimize its effectiveness at physiologic serum levels for prophylaxis for ROP. Also presented are the promising results of our experience with vitamin E at pharmacologic serum levels as a treatment for severe ROP (defined as in the Cryo ROP Trial). These indicate the need for a multicenter trial to assess the effect of pharmacologic Vitamin E therapy as an alternative or supplement to therapy of severe ROP with laser or cryo surgery.