Sterols are major components of many biomembranes and are known to play an important role in several biological processes. In order to understand the complex lipid-sterol interactions and their influence on membrane structure and properties, model membranes containing cholesterol and other sterols have been widely studied using a variety of experimental techniques. This chapter gives a brief review of X-ray and neutron scattering studies of these systems, highlighting the detailed structural information they provide. © 2010 Elsevier Inc.