To create a pose-invariant face recognizer, one strategy is the view-based approach, which uses a set of example views at different poses. But what if we only have one example view available, such as a scanned passport photo -- can we still recognize faces under different poses? Given one example view at a known pose, it is still possible to use the view-based approach by exploiting prior knowledge of faces to generate virtual views, or views of the face as seen from different poses. To represent prior knowledge, we use 2D example views of prototype faces under different rotations. We will develop example-based techniques for applying the rotation seen in the prototypes to essentially "rotate" the single real view which is available. Next, the combined set of one real and multiple virtual views is used as example views in a view-based, pose-invariant face recognizer. Our experiments suggest that for expressing prior knowledge of faces, 2D example-based approaches should be considered ..