There is a tendency for the posterior chamber intraocular lens to tilt about the points of insertion. This is found clinically and in postmortem studies of eyes that have had intraocular lenses surgically implanted. One end is often located in the lens capsule and the other end is located in the ciliary sulcus. The possibility of anteroposterior displacement also exists. Using a modified Gullstrand schematic model eye, we have computed the amount of spherical and cylindrical errors that are induced due to the tilt and/or displacement of the intraocular lens. If a cylindrical error of approximately 90 degrees from the axis of insertion (lens plus haptic loops) and/or axis of tilt is detected, further careful investigation is warranted.