In response to the growing popularity of content-based language teaching models both in the United States and abroad, this text documents well-established programs at the post-secondary level and provides a rationale for content-based instruction. Three different approaches -theme-based, sheltered, and adjunct- are examined, as well as the extent to which they share basic underlying features. The text presents profiles of several exemplary programs, explores the kinds of populations and settings most appropiate for the different models, and discusses the administrative considerations in their implementation. In addition, it offers detailed guidelines for teachers who would like to design their own content-based curriculum, including information on how to evaluate and place students and how to develop appropiate materials for specific subject matter content.