As the temperatures continue to rise in Los Angeles, the lovely ladies of Hollywood are stepping out in looks celebrating the season and we like what we see. This week alone boasted loads of celebrities showing off spring's hottest trends and styles, from peplums and sheer cutouts to crop tops, at parties all over town. See the stylish women who worked our top 10 party looks of the week in this installment of Best Dressed Guests.

New Yorkers closed out the week in style at events all around the city last night. From an A-list birthday bash for Aby Rosen at the Paramount Hotel to a chicrooftop celebration for the Perrin Paris 1893 NYC launch, there was no shortage of fashionable ladies to choose from for today's best dressed guests roundup. Click through to see the amazing looks from Thursday night for yourself.

David Arquette and Carmen Electra kick it with Perez Hilton at his CD release party at Bootsy Bellows; Caroline D'Amore, Diana Madison, and L.A. media mavens step out for the Rev New Media open house; Courtney Stodden, Shekhar Rahate, and Buzz Aldrin hit up Dr. Ava Cadell's Sizzling Sexy Summer Event; Jennifer Morrison, Vanessa Hudgens, and Audrina Patridge get their hair styled at the Nine Zero One Salon; Julia Louis-Dreyfus, Amy Smart, Ed Begley Jr., and other environmentalist notables support Heal the Bay's Bring Back the Beach Annual Gala; Kerry Washington, Katie Lowes and "Scandal" co-stars walk the red carpet for the season finale celebration—get your final L.A. event rundown of the week in this edition of Last Night's Parties.

Last night in NYC, Bono, Owen Wilson, and the Olsens celebrate Aby Rosen's birthday at the Paramount Hotel, Perrin Paris 1893 celebrated their New York launch at the Terrace Penthouse, Andy Cohen and Allison Sarofim hosted the first annual Hero Fund Scholarship, and so much more!

The 66th Annual Cannes Film Festival officially kicked off on Wednesday, as the glitterati donned their red carpet best to attend the "Great Gatsby" screening at the 2013 opening ceremony. All of our favorites, from Cara Delevingne to Carey Mulligan, arrived in the French Riviera, ready for the glamorous 12 days ahead. Click through to see some of the gorgeous looks that kicked off the festivities.

In 2008 Surf Lodge, a quaint restaurant with a surf theme opened on Fort Pond with hardly much of a bang. Sure they had a hip chef running the kitchen and a verified Manhattan nightlife crew running the party scene, but the hundreds of cars and frat boys would take a year or two to fully figure out what was brewing in Montauk. Since then, the movement of the hampters (hipsters from Manhattan) and the share house yuppies looking to party in the Hamptons has consistently headed East (Luckily for Lizzie Grubman, Conscious Point isn't even a memory in the minds of current trend-seekers). Keeping on trend, Montauk's nightlife scene will continue to dominate the Hamptons this summer, despite the growing battle between the townsfolk and these summer subversives who will be infiltrating their territory come Memorial Day weekend. But we're not here to take sides, we're here to report. Check out our official guide to Hamptons Nightlife 2013! More»

If you look at the lives of fashion designers, it becomes clear that their creativity and design stretch far beyond their collections. From the Neolithic styling of the avant-garde Rick Owens to the cowboy mecca of Ralph Lauren, take a look at these designers incredible homes!

Planning for the weeks ahead? Head over to the MoMA for their Annual Party in the Garden, discover the most promising new companies at Time Inc.'s 10 NYC Start-ups to Watch Party, and hear Jennifer Hudson perform at the 92Y Annual Spring Gala. Here are 10 parties to put on your radar. More»

Planning for the weeks ahead? Head over to The Beverly Hilton for The Gracies Awards, join the Asian Pacific Women's Center at Walt Disney Concert Hall for their 11th Annual Metamorphosis Gala, and celebrate LA Waterkeeper's 20 years of protecting L.A. waterways at Making Waves 2013! Here are 10 can't miss parties and events to put on your radar. More»

Derek Hough, Miley Cyrus, Kendra Wilkinson and many more celebrate Maxim's Hot 100 of 2013 in Hollywood; Kelly Osbourne, Matthew Mosshart and Josh Flagg kick off amfAR's generationCURE to support HIV/AIDS research for a cure; Mark Mothersbaugh and a slew of other music industry giants help honor entertainment's most distinguished composers such as Mike Post, Cliff Martinez, and John Williams at the BMI Film & TV Awards; Mike Epps throws out the first pitch at Dodger Stadium—get the details on Hump Day's top happenings in this installment of Last Night's Parties.

Last night in NYC, Donatella Versace presented the New Versus Versace to a star-studded crowd, including Heidi Klum, Taylor Momsen, and Mena Suvari, HRH Prince Harry of Wales scored the winning goal at the Sentebale Polo Cup, Elle Editor-in-Chief Robbie Myers hosted an intimate dinner for Kerry Washington to celebrate her as June Elle’s cover girl, and so much more!