Posterior capsular opacification (PCO) is the most frequent complication of cataract surgery. Advances in surgical techniques, intraocular lens materials, and designs have reduced the PCO rate, but it is still a significant problem. The only effective treatment for PCO, Nd:YAG laser capsulotomy carries vision-related complications and risks and puts a significant financial burden on the health care system. This review contains current knowledge about the mechanisms of PCO development. Posterior capsular opacification is caused mainly by remnant lens epithelial cell proliferation and migration, epithelial-mesenchymal transition, collagen deposition, and lens fiber generation. All of these processes are influenced by cytokines, growth factors, and extracellular matrix proteins. We also describe advances and improvements in surgical techniques, intraocular lens materials, and the designs and use of therapeutic agents leading to safe, effective, and less expensive strategies to eradicate PCO.