This training guide has been developed for use by staff members of the U.S. Marine Corps, Office of Manpower Utilization in their preparation for Task Analysis projects, the first step in a research program aimed at increasing the effectiveness of the Marine Corps' manpower management program. The guide is designed to provide basic orientation to Task Analysis and detailed suggestions for carrying out the entire observation and interview phase of the Task Analysis process. The background of experience in job analysis is described in terms of the most common methods and their advantages and limitations. Special attention is directed to requirements of reliability and validity and to recommended procedures for meeting these requirements. To ensure the quality of findings in Task Analysis studies of Marine Corps Occupational Fields, specific recommendations are given for all major steps in the data-gathering process including improving interviews by checking questions, building respondent motivation, developing listening ability, managing the interview, and improving both observation and the recording of information. (Author/WL)