Endogenous endophthalmitis still presents a diagnostic and therapeutic challenge even with improvements in therapeutic modalities. The main prognostic factor is the virulence of the causative organism: once the organism enters the eye, it rapidly destroys ocular tissues. With the increasing ability to prolong the life of very ill patients, incidence of endogenous endophthalmitis is expected to increase. Ophthalmologists must be ever more vigilant, because prompt treatment offers the best chance of saving the eye.