The main purpose of the handbook is to provide occupational information that broadens the knowledge of choices available to young people and helps them make intelligent career plans. It is also a useful resource for persons entering or reentering the work force at different stages of their lives. For hundreds of occupations the handbook answers such questions as: What does a person actually do on the job? What abilities and interests does the job call for? What are the working conditions like? What will be the job opportunities in coming years? This edition of the handbook presents occupational materials in new clustering system designed to organize occupations by related activities. The new Handbook also includes expanded earnings information, additional information on job characteristics as they relate to young people's interests and abilities, and finally an extensively revised guide on how to use the handbook for career guidance. (Author)