Harry Levinson, a psychologist who helped change corporate America’s thinking about the workplace by demonstrating a link between job conditions and emotional health — a progressive notion when he began developing his ideas in the 1950s — died on Tuesday in Delray Beach, Fla. He was 90.

His death was confirmed by his son Marc.

As a management consultant and an educator at Harvard, M.I.T. and other universities, and through books, seminars and his own research institute, Dr. Levinson showed how psychoanalytical theories and methods could be used to motivate employees. He was among the first psychologists to postulate a connection between thwarted career aspirations and depression....