Establishment of the federal-state Employment Service system created a need for a standardized occupational language to ensure uniform matching of workers with jobs. The Occupational Analysis Research Program was initiated to gather a broad base of detailed occupational information. Although the organizational structure of all editions of the Dictionary of Occupational Titles (DOT) has differed to varying degrees, the basic intent has remained to identify jobs and provide a tool for the employment service to match workers with jobs. Today's users and uses extend far beyond that basic intent. The DOT is widely used by educational institutions, government agencies, companies, and nonprofit agencies for career and vocational counseling, library reference, rehabilitation counseling, personnel management, employment placement, and research. Data collection has an industry approach. Research efforts are focused on the study of selected industries to document jobs that have undergone the most significant changes. Terms used in job analysis have definitions developed by the U.S. Employment Service. The job analysis method approved for use by the Employment Service recognizes two major dimensions of job information--Work Performed and Worker Characteristics. A combination of observation and interview is the traditional method of data collection. Individual job analysis reports are evaluated and grouped, based on analysis of tasks performed, for use in formulating and writing occupational definitions. (YLB)