&NA;New insight into the pathophysiological mechanisms of immunologic and inflammatory ocular disease has emerged. Although many of these diseases continue to be an etiological enigma, recent investigation has provided important clues toward solving years of mystery. Antiphospholipid antibodies have been implicated in vasoocclusive events. A gene candidate responsible for susceptibility to Behcet's disease has been suggested. Unusual manifestations of giant cell arteritis, sarcoidosis, and Wegener's granulomatosis are reported. In ocular allergy, the pathophysiologic role of mast cells in atopic keratoconjunctivitis and eosinophils in vernal corneal ulcers are presented. A quantitative scoring system for grading the severity of scleritis and treatment response is described. A T‐cell abnormality possibly specific to primary sjÖgren's syndrome is discovered.Current Opinion in Ophthalmology 1993,4;VI:106‐112