Kourtney Kardashian was the hostess with the mostess in retro-inspired swimsuits at her own Poosh party, thrown at the lifestyle blogger’s Calabasas mansion. A-list guests like Suki Waterhouse joined Kourt by the pool!

Kourtney Kardashian, 40, knows how to throw a party — and how to dress for one. In honor of her new Poosh lifestyle blog, which launched on April 2, the Keeping Up with the Kardashians star opened her Calabasas lawn and pool to celebrity guests like Rosie Huntington-Whiteley, Suki Waterhouse, Kris Jenner, Yris Palmer, Adrienne Bailon, Nicole Williams, Rachel Roy, Melissa Alcantara and two famous pairs of twins, Malika and Khadijah Haqq, and Simi and Haze Khadra, on Sept. 14. It was a luxurious affair, dubbed the “End of the Summer Wellness Celebration,” and called for two outfit changes from the hostess.

Kourtney partied alongside her guests in a yellow polka dot one-piece suit, a piece you’d expect to see on the shore of Surf City USA in the mid-20th century! A beehive bump, thick headband and cat-eye sunnies completed Kourtney’s tribute to the ’60s, which she continued with yet another retro suit: a two-piece striped yellow set. The second suit showed off more of her curves, which featured an underwire cup top and high-waisted bottoms. The guests rocked similar suits, thank to complementary swimwear from Onia. The throwback theme was intentional — she wanted the vibe to be “Slim Aarons-meets-Beverly Hills hotel, but with a vintage twist,” according to her Poosh blog post about the party.

Kourtney and her guests were pampered in true Kardashian style. The party agenda included visiting the Stuart Weitzman clubhouse to nab customized sneakers, facials and massages while relaxing on Avocado mattresses on Kourt’s basketball court, a yoga class led by Melissa Alcantara, and a tea ceremony that Kourtney’s daughter, Penelope Disick, 7, joined! It makes sense that Penelope would score an invite to her mom’s party, seeing that the blog is named after her (Penelope’s nickname is Poosh).

Kourtney Kardashian
This may be Kourtney Kardashian’s backyard in Calabasas, but she’s transporting us back to a pool somewhere in Palm Springs in the ’60s! (Poosh/Katie Levine/MEGA)
Kourtney Kardashian
Kourtney Kardashian enjoys a day of poolside glamour with her close friends at her Poosh party on Sept. 14, 2019. (Poosh/Katie Levine/MEGA)

Kourtney will continue to celebrate the successes of Poosh by taking the stage at Create & Cultivate San Francisco on Sept. 31. The professional conference invited the mother of three to talk about her “journey” building Poosh, and what it’s like to be a “modern woman and a working mommy,” Kourtney revealed in an Instagram post on Sept. 17.