The field of nonlinear optics has grown significantly within the last two decades. Photorefractive materials in particular have been utilized in a wide variety of applications. Recently, the photorefractive inorganic crystals used to demonstrate nonlinear optical phenomena and applications have begun to decrease significantly in cost, bringing them within the budgetary limits of smaller physics departments. In addition, within the last five years photorefractive organic polymers have been developed which could serve as the focus of interesting interdisciplinary activities between undergraduate physics and chemistry programs. This article provides a starting point for educators in such programs who have an interest in developing undergraduate laboratory projects based on photorefractive materials. We present some background on the physics of photorefractive phenomena and materials, brief descriptions of some of the demonstrations and applications that employ these materials, and original references on these applications. (C) 1997 American Association of Physics Teachers.