Semhon began her career in the beauty industry as a cosmetics buyer at B. Altman, moving on to Lauder as a sales executive and then becoming national vice president of sales at Helena Rubinstein. She subsequently led the sales force at Parlux during the introduction of Giorgio Armani women's and men's scents in the mid-Eighties. She was also responsible for the Anne Klein 2 fragrance launch, as well as fragrance introductions by Francesco Smalto and Joan Collins in the late-Eighties.
As a marketer, Semhon developed color cosmetics for Orlane and home shopping channels QVC and HSN, working on product development at Private Label Cosmetics, a firm owned from about 1990 to 1995 by her husband, Gerard Semhon.
Recently, she was a partner with her husband in Beauty Options Ltd., where Gerard Semhon is chief executive officer. The firm specializes in mergers and acquisitions and new product development worldwide within the beauty industry. One of the firm's current projects in Dubai took the husband-and-wife team there frequently and Diane Semhon fell in love with the area.
Additionally, Semhon, who was politically active, worked for the election of Andrew Cuomo as New York Attorney General.
She is survived by her husband; her mother, Bernice Zohoski; a sister, Alison Johanson; a brother, Wayne Zohoski, and a niece, Ashley.