Founded public relations agency Clein + Feldman in 1981 with Bruce Feldman. When Feldman left in 1989 and Cara White joined the firm, the name was changed to Clein + White.
Received the 2000 Publicists Guild Career Achievement Award for his work on The Blair Witch Project.
Began his professional career as a page at NBC in New York.
When Clein relocated to Los Angeles, he worked for a detective agency posing as an employee at Disneyland one summer.
Began he media career working for LA gossip columnist Joyce Haber.
As a journalist he wrote for the Los Angeles Times, TV Guide, Show and Coast magazines. He was also the film critic for the trade publication Entertainment World.
Began his public relations career at Pickwick Public Relations under Pat Kingsley and Lois Smith. His clients included Steve McQueen and Ali McGraw, Candice Bergen, Bette Midler and Liza Minnelli.
Taught film marketing and publicity to Producing students at American Film Institute in Los Angeles, California.