As it goes with summer weekends in New York, there was a mass celebrity exodus to the Hamptons this week. Rachel Zoe and Kourtney Kardashian showed up in East Hampton for an elegant dinner to celebrate Baby Buggy (sponsored by Giorgio Armani), while Joshua Jackson kept it casual at Surf Lodge in Montauk for Daniel Arsham’s art studio show. Alec Baldwin spent the day with his family at the Ovarian Cancer Research Fund’s Super Saturday benefit, and Kelly Rutherford joined Holly Peterson to celebrate Elle Decor’s newest issue. Meanwhile, on the West Coast, Rose McGowan attended Maison Martin Margiela’s ready-to-wear spring 2014 party in L.A. Click through the slideshow for these and more highlights from this week’s parties.