The nine aptitudes measured by the General Aptitude Test Battery (GATB) are intelligence, verbal aptitude, numerical aptitude, spatial aptitude, form perception, clerical perception, motor coordination, finger dexterity; and manual dexterity. This revised test manual presents: (1) percentile equivalents of aptitude or standard scores for adults, tenth graders, and ninth graders; (2) minimum intelligence scores as predictors of success in junior college, four-year college, and professional education; (3) a description of the Occupational Aptitude Pattern Structure (OAP), which displays GATB norms for the three age groups; (4) the standard error of measurement of the GATB; (5) OAP's, 1,100 occupations; (6) six important researched jobs not incorporated into the OAP; (7) an alphabetical index of occupations; and (8) a list of worker trait groups and OAP's in which they appear. The OAP's consist of the most significant aptitudes and the critical scores established as minimum (cutting) scores for a group of occupations having similar aptitude requirements. The titles and numerical codes for the occupations are taken from the Dictionary of Occupational Titles (CP)