The firm has made up just one female partner, Helen Croke, since 2007.
Henderson’s departure means the employment team she set up has shrunk from five to three partners in a matter of months.
Incoming managing partner Andrew Lilley is currently included in the team, but will leave to take up his new role in January. Tim Gilbert made partner in the practice in July, joining partners Richard Baty and Sian Keall.
Travers’ current managing partner Chris Carroll said Lilley would continue to work closely with the employment team, but that the remaining partners would have to reduce their support work for other practice areas.
Henderson will continue to work part-time as an employment tribunal judge.