The objective of this study is for the contractor to support the epidemiologic research of the EEB in the following ways: by the conduct of multiple epidemiologic studies, by the maintenance, acquisition and use of epidemiologic data bases, by provision of support for specimen collection and laboratory aspects and by responding qickly to requests from the Project Officer involving certain priorities. The types of activities needed in the conduct of specific studies can be divided into seven tasks: Task 1 - Initiation and Liaison Task 2 - Development of Study Materials and Procedures Task 3 - Identifying and Tracing Study Subjects, Data Collection and Monitoring Task 4 - Data Preparation Task 5 - Data Processing Task 6 - Documentation, Monitoring, Quality Control, and Priority Actions Task 7 - Laboratory Aspects Involving Biologic Specimens and Tests