The fourth season of the romantic comedy-drama Sex and the City marks dramatic changes in the ladies' lives. Carrie gets back together with Aidan (John Corbett), eventually gets engaged, and has him move in with her. Miranda, while maintaining her single life, supports Steve (David Eigenberg) through cancer and, after a one-night stand with him, becomes pregnant. Samantha dates a Brazilian lesbian artist Maria (Sônia Braga) and starts a serious relationship with her client and hotelier Richard (James Remar). Charlotte gets back together with Trey (Kyle MacLachlan) after their separation and after deciding to have a baby, struggles to get pregnant and ultimately separate for good.
Cameo appearances from comedienne Margaret Cho, Alan Cumming, supermodel Heidi Klum, Ed Koch, Tony Hale, Kevyn Aucoin, Domenico Dolce, and Stefano Gabbana. Lucy Liu appeared as herself in the episode "Coulda, Woulda, Shoulda". In the episode "A 'Vogue' Idea", Candice Bergen portrayed Enid Mead, Carrie's publisher at Vogue magazine. Ron Rifkin played Carrie's boss Julian in the episode.