Ziering was Playboy's Playmate of the Month for September 1997. She appeared on the cover twice, first in August 1997, then in July 2003, along with a feature pictorial. Prior to Playboy, Ziering was a swimwear model usually modeling for Venus Swimwear and Frederick's of Hollywood. She appeared as a Barker's Beauty on The Price Is Right from 1999 to 2002, and from 2000 until her departure she assumed previous fellow model Janice Pennington's role as mic handoff girl because after Janice and Kathleen Bradley's departure she was the then longest tenured model. Ever since Nikki's departure a different model has handed off the mic to Bob/Drew each day as the rotation cast of models was implemented in the wake of her departure along with fellow models Heather Kozar and Claudia Jordan leaving as well.