Technological change is a complex term involving many more factors than "changes in machinery or automation." Six changes which affect jobs and influence skills in our industrial systems that could logically be called technological change have been identified: (1) scientific management, or time and motion studies, (2) mergers and consolidations, (3) changes in the locations of plants, (4) shifts in product demand, (5) changes in machinery and technology, and (6) automation. A review of the literature does not reveal a neat group of hypotheses that can be clearly delineated. However, four major problem areas have received repeated attention: the factors affecting reemployment of displaced workers, the process of finding a job, the mobility of displaced workers, and the economic and non-economic consequences of job displacement. (CH)