The Survey Methods Core will be responsible for sampling, data collection, and data management for this program project. It will also be responsible for working with all investigators in pretesting and developing final versions of all survey instruments. Through this core, all common data items will be tracked to ensure that they are maintained in a common format to allow comparability across projects. Data files and data documentation will be prepared and then provided to the Biostatistical Core for analysis and maintenance. The substantial array of consultative and direct services provided by this core resource will be subcontracted to the Survey Research Laboratory of the University of Illinois. Significant features of this core resource include the extensive collaboration with the CIS Research Consortium senior leadership in the development of the overall program project application, the extensive instrument development and pretesting procedures outlined herein, and the substantial attention given to control and coordination of timelines among the component projects included in this program project.