Dana Lambert was a member of the IMF. She succeeded Cinnamon Carter in the IMF for a brief time before being replaced herself by Lisa Casey. She was portrayed by Lesley Ann Warren (who was credited as Lesley Warren on the series).
Unlike Cinammon's cool, collected (sometimes sardonic) demeanour, Dana was generally depicted as more serious and solemn (rarely smiling outside of playing an undercover character). Her youthful attractiveness was also called upon on numerous occasions to seduce or at least emotionally engage with targets, a notable example being in the episode "Flip Side" in which Dana feigns romantic intention towards a much older man in order to execute the mission. Dana was also an accomplished singer (as is Warren in real life), though this was primarily only featured in the aforementioned "Flip Side".
Although Dana's age is never revealed, Warren was 24 at the time Season 5 of Mission: Impossible was broadcast, making her the youngest regular member of the IMF in the TV series.