The book contains papers presented at a July 1973 conference sponsored by the Engineering Foundation of New York City, the American Psychological Association, and the Engineering Foundation for Professional Development. The papers examine the psychological and motivational changes which occur in midcareer engineers (Approximately age 40), with respect to the engineering profession's desire to maintain a high level of performance in post-midcareer engineers. The first of five sections contains five papers concerned with defining and isolating the factors involved in technical obsolescence and updating. In the second section, four papers present results of recent studies which refute the misconceptions generally held of the declining capabilities, adaptation, and motivation with increasing age. In the third section on training and retraining, four papers deal with individualization of instruction, computer-assisted instruction, self-directed career planning, and Federal government retraining programs. The fourth section (two papers) deals with work motivation and updating and organizational climate factors which can stimulate professional growth. In the fifth section, four papers describe specific industry, government, university, and professional society continuing education programs. The final section (two papers) discusses new approaches to improving the competence of older professionals along the lines of job enrichment and job redesign. (JR)