The incidence of posterior capsule opacification (PCO), the most common complication of modern cataract surgery with intraocular lens implantation, seems to have decreased slightly as a result of improved surgical and cortical cleanup techniques. However, the reported incidence is still significant. The diverse findings on PCO are the result in part of studies using different criteria to clinically judge and quantify the condition. In addition, the influence of intraocular and systemic factors are only now being identified. This second of a 2-part review of PCO focuses on (1) less subjective morphological and patient-dependent means to evaluate and quantify PCO; (2) the influence of ocular factors on PCO; (3) the influence of systemic factors on PCO; (4) available means and approaches to prevent or delay PCO.