A high speed rail system is being proposed for the California Corridor. This research seeks to develop a methodology for predicting the level of demand for such a service. A methodological review and evaluation of discrete choice models and their assumptions,, both explicit and implicit, provides the foundation for the development of a survey design. A framework for demand estimation is provided as a basis for focusing attention on a revealed preference survey of travel patterns in California. The survey design consists of both a sampling plan and a questionnaire design that will enable the collection of the information needed to predict the effect that high speed rail will have on the existing transportation environment. The survey design proposed provides an implementable method for collecting the data necessary to estimate the demand for high speed rail, as well as other modes, in California accurately using state-of-the-art modeling techniques.