The functional results after pediatric cataract surgery depend not only on the anatomic success of the operation and postoperative maintenance of a clear optical axis, but even more on aphakic visual rehabilitation. Children's eyes with cataract severe enough to require cataract extraction usually have some degree of amblyopia already present prior to surgery. In unilateral pseudophakia amblyopia develops postoperatively unless the fellow eye is occluded or optically and/or pharmacologically penalized. Immediate optical correction is desirable because prevention and/or therapy of amblyopia should be initiated directly after surgery. Parental compliance with occlusion therapy and not successful surgery are major determinants of a good visual outcome in unilateral aphakic/pseudophakic children.