Whipped 1998 on netflix

Noted documentary filmmakers Iana Porter and Sasha Waters direct this understated and decidedly un-exploitative look at the world of sadomasochism both as therapy and as business. The film focuses on three New York dominatrices who willingly, lovingly, flog, smack, and abuse their clients: young perky Carrie, glitzy 30-something Sonja Blaze, and Teutonic matron Eva. All argue that they are providing society with an important, if quasi-sexual, service. Their clients ardently agree.