The 36th annual Hamptons Classic Horse Show-a summer favorite-culminates with the VIP Grand Prix Day. Regular attendees in recent years have included Mayor Bloomberg, Alec Baldwin, Christie Brinkley, Bruce Springsteen, Kelly Ripa, and Kelly Klein. 8 a.m. Call: 631-537-3177.

Fashion's Night Out'the after-hours shopping extravaganza?is back! For the third year in a row, celebrities, designers, and performers will mingle with shoppers as they take part in exclusive events and snap up special designs. 6 p.m. Visit www. fashionsnightout.com for more information

It's all about the kids at the New Yorkers for Children Fall Gala. Join chairs Vanessa and Henry Cornell, Oscar de la Renta, Lise and Michael Evans, Kevin and Erika Liles, Ashley and Jeff McDermott, Shirin von Wulffen, and Frédéric Fekkai for dinner, dancing, a live auction, and a special musical performance. 6:30 p.m. Cipriani 42nd Street. Call: 212-867-1117.

Alan Gilbert conducts the NY Philharmonic Opening Night Celebration, Live From Lincoln Center, with soprano Deborah Voigt. The kickoff of the 170th season will be music to your ears! 7:30 p.m. Avery Fisher Hall at Lincoln Center. Call: 212-875-5757.

Avenue Shows hosts the Antiques, Art, and Design event at the Park Avenue Armory. Join chairs Ellie Cullman and Jamie Drake, as well as several leading designers for the opening night party on September 21. Angelo Donghia, president of luxury furnishings brand Donghia, will present the first-ever lecture to late legacy Crans Baldwin. Park Avenue Armory. Call: 212-284-9728.

Join Sir Paul McCartney and ballet master- in-chief Peter Martins for the New York City Ballet Fall Gala. The must-see performance of Ocean?s Kingdom will kick off the company?s 2011-2012 season. 7 p.m. David H. Koch Theater at Lincoln Center. Call: 212-870-5570.

The Mario Batali Foundation and Vanity Fair are teaming up to host an exclusive evening of exquisite food, wine, and entertainment. Come enjoy a walk-around sumptuous tasting and a live auction to support the foundation?s efforts to ensure that children are well cared for! 7:30 p.m. City Winery. Call: 773-679-1633.

The 26th annual Great Sports Legends Dinner will benefit the Buoniconti Fund, a fundraising arm of the Miami Project to Cure Paralysis. Guests will be entered to win a seven-day cruise for two! 5:30 p.m. The Waldorf. Call: 305-243-4656.

Just in time for harvest season! Support local farmers at the second annual Art of Farming event. Dive into the delicious hors d?oeuvres by Rouge Tomate and a buffet- style dinner by NYC's top chefs. 7 p.m. Sotheby's. Call: 212-829-0002.

The Film Society of Lincoln Center presents its 49th annual New York Film Festival, which continues through October 16. Events are planned for Alice Tully Hall, the Walter Reade Theater, and the Elinor Bunin Munroe Film Center at Lincoln Center. For tickets and show times, call: 212-875-5601.

The Film Society of Lincoln Center presents its 49th annual New York Film Festival, which continues through October 16. Events are planned for Alice Tully Hall, the Walter Reade Theater, and the Elinor Bunin Munroe Film Center at Lincoln Center. For tickets and show times, call: 212-875-5601.

Mount Sinai Breast Health Resource Program hosts the 19th annual Celebration of Life Gala. Dress in your chicest cocktail attire to honor Drs. Laurie Margolies and Georgia Witkin. 7 p.m. The Pierre. Call: 212-824-8250

The Police Athletic League hosts the 6th annual Building New York's Future Luncheon. 11:45 a.m. The Pierre. Call: 212-477-9450.

The NY Stem Cell Foundation hosts the sixth annual Translational Stem Cell Research Conference, chaired by Lee Goldman, Antonio Gotto, Douglas Melton, Allen Spiegal, and Irving Weissman. 9:30 a.m. Rockefeller University. Call: 212-365-744

Check out the most cutting-edge jewelry designs at one of the Museum of Arts and Design's most popular events-Loot! 2011. Join honorary chair Robert Lee Morris to benefit the museum's exhibitions and education programs. Times vary according to ticket level. Museum of Arts and Design. Call: 212-299-7712.

Dress in your finest cocktail attire for NY Presbyterian Hospital's Cabaret Gala and enjoy a fabulous performance by Kelli O'Hara. 6:30 p.m. Park Avenue Armory. Call: 914-235-1490 ext. 14.

Alec Baldwin hosts the 19th annual Hamptons International Film Festival. Limited-edition posters by artists Julian Schnabel, Ross Bleckner, Cindy Sherman, Eric Fischl, and Malcolm Morley will be on display, with some available for purchase! Visit www.hamptonsfilmfest.org for event updates and tickets, or call: 646-861-0843

The Annual Autumn Dinner, one of the most memorable parties of the year, honors Anne Poulet, retiring director of the Frick Collection. 7 p.m. The Frick. Call: 212-547-076

Join hosts Denise Rich, Danielle Rich Kilstock, and Ilona Rich Schachter at Gabrielle's Angel Foundation for Cancer Research Angel Ball. The gala honors artists Romero Britto and Vladislav Doronin. 6:30 p.m. Cipriani Wall Street. Call: 212-744-5022

Sink your teeth into the City Harvest at its 17th annual Bid Against Hunger restaurant tasting. 7:30 p.m. Metropolitan Pavilion. Call: 212-843-807

The American Museum of Natural History hosts the 18th annual family party, one of the museum's best-loved traditions. Join the family fun, including entertainment by the Laughing Pizza Band. Museum of Natural History. 5 p.m. Call: 212-313-716

Join gala chairs Princess Yasmin Aga Khan and Jay and Anne Hearst McInerney as the Alzheimer's Association hosts the Rita Hayworth Gala, themed ?"Hollywood Glamour." Enjoy dinner and dancing as Somers Farkas and HSNi's Mindy Grossman are honored! 6:30 p.m. The Waldorf. Call: 212-843-1712

The Elton John AIDS Foundation's An Enduring Vision honors John Demsey, Greg Gorman, and Bob and Tamar Manoukian. 7 p.m. Cipriani Wall Street. Call: 212-219-029

The Breast Cancer Research Foundation will host its annual Symposium and Awards Luncheon. Join chairs Robert Amon, Anne Bass, Susan Payson Burke, Betsey Green, Joanne de Guardiolo, and Ronnie Heyman as Richard Anderson and Mina Bissell are honored. 9:45 a.m. The Waldorf. Call: 646-497-2620.

Support UNICEF at the Masquerade Ball. Join chairs Danielle Abraham, Gillian Hearst Simonds, and John Kluge for a ball you won't want to miss! 8 p.m. Angel Orensanz Foundation at 172 Norfolk Street. Call: 212-880-9139.

Rolex presents Career Transition for Dancers 26th anniversary gala, A Halloween Thriller-a dance celebration of ghosts, ghouls, and vampires. The thrilling performance will astonish guests with fun and spine-tingling works from America's greatest dance companies and Broadway? woven together in a "spooktacular" celebration of dance! 7 p.m. New York City Center. Call: 212-228-7446.

The Princess Grace Foundation hosts its annual awards gala, honoring recipients for artistic excellence in theater, dance, and film. 6:30 p.m. Cipriani 42nd Street. Call: 212-245-6570.

Liz Smith hosts a black-tie gala for the New York Conservancy Living Landmarks Celebration, honoring Lewis Cullman, Louise Kerz Hirschfeld, Angela Lansbury, Danny Meyer, and former NYC Mayor David Dinkins. 7 p.m. The Plaza. Call: 888-850-0909.

It's all about art at the Children's Museum of Art's seventh annual Art Auction. Join chairs Simon de Pury, Yvonne Force Villareal, Cynthia Rowley, and Bill Powers, along with artist chair Matthew Ritchie, to bid on fabulous pieces. 7 p.m. 82 Mercer. Call: 212-868-8450.

Join chairs Jacqueline Weld Drake, Aileen Mehle, and Prince Dimitri of Yugoslavia at Casita Maria's annual fiesta. Get in on the glam for this joyful celebration. 7:30 p.m. Mandarin Hotel. Call: 212-573-6933.

Library Lions' black-tie gala honors Jonathan Franzen, Natalie Merchant, Ian McEwan, Isabelle Wilkarson, Stacy Shiff, and Tony Kushner. 7 p.m. Stephen A. Schwarzman Building at the New York Public Library. Call: 212-262-7444.

Join emcee Liz Smith and chair Diana Taylor for the Police Athletic League's 24th annual Women of the Year Luncheon to honor Dolly Lenz. 11:30 a.m. The Pierre. Call: 212-477-9450

The ACE Awards (Accessories Council Excellence) honors those who made great strides in raising awareness of the accessories industry. 6:30 p.m. Cipriani 42nd St. Call: 212-947-1135

The American Ballet Theater returns with the premiere of new works by Demis Volpi, Merce Cunningham, Paul Taylor, and Martha Clarke. The opening night gala runs for eight consecutive nights. City Center. For performance times and more information, Call: 212-477-3030

Chairs Kitty and Tom Kempner, Suzanne and Woody Johnson, Gillian and Sylvester Miniter, and Fiona and Eric Rudin host the Central Park Conservancy?s Autumn Dinner and Dance Party. 7 p.m. Tavern on the Green. Call: 212-310-6619

Dress in your foxiest attire for the Michael J. Fox Foundation's annual A Funny Thing Happened on the Way to a Cure Benefit to support the foundation's mission to find a cure for Parkinson?s disease. 7 p.m. The Waldorf. Call: 212-245-6570.

An extraordinary evening awaits you, as renowned chef Jeremy Bearman is honored at the Pony Awards, followed by a surprise guest performance! 7:30 p.m. Rouge Tomate Call: 917-612-6161

The Visionaries! Gala benefit honors former chairman of Hermès Jean-Louis Dumas, Benjamin Moore honcho Denis Abrams, Robert King, and designer Vladimir Kagan for dinner, an exquisite live auction, and award ceremony. 6:30 p.m. Museum of Arts and Design. Call: 212-299-7712

The U.S. Fund for UNICEF hosts its annual black-tie Snowflake Ball to honor those whose humanitarian commitments support the foundation?s mission to save children's lives. Join chairs Pamela Fiori and Charlotte Moss, as well as NY's most prominent philanthropists. Call: 212-880-9131.

The Christopher and Dana Reeve Foundation marks its 21st anniversary with A Magical Evening gala. Join Kiernan Ventures chief exec Peter Kiernan, along with World Golf Hall-of-Famer Karrie Webb, as they are honored for their courageous spirit and hope. 6:30 p.m. Cipriani Wall Street. Call: 973-379-2690.

Dance the night away as Lenox Hill Neighborhood House hosts its Associates Committee Benefit! Cocktails are at 8 p.m. and dinner and dancing are at 9. The Union Club. Call: 212-744-5022 ext. 1237.

Get into the holiday spirit at the Nutcracker Family Benefit. Join chairs Joyce Giuffra, Julia Koch, and Elizabeth Miller for a matinee performance of George Balanchine's The Nutcracker, as well as a post-performance holiday party on the Promenade. 2 p.m. David H. Koch Theater at Lincoln Center. Call: 212-769-6610.

It's puppy love at the Animal Medical Center's Top Dog Gala as Diana Taylor is honored with the Center?s Brooke Astor Award. 7 p.m. Cipriani 42nd Street. Call: 212-329-8666.

Join Harold Koplewicz and chairs Brooke Garber Neidich and Debra Perelman the second annual Child Mind Institute's Child Advocacy Award Dinner to raise awareness of mental health initiatives for children around the world. 6 p.m. Cipriani 42nd Street. Call: 212-245-6570.

Attend the French Institute's 2011 Trophee des Arts Gala. Enjoy cocktails, dinner, and a live auction honoring Paul Desmarais. The black-tie event benefits the institute?s world-class educational and cultural programs. 7 p.m. 583 Park Ave. Call: 646-388-6604.