• Meet designer Stella McCartney and preview her fall 2011 collection during the launch of her new shop at Saks. Actress Liv Tyler hosts a cocktail reception in honor of the designer, and guests can enjoy complimentary cocktails, hors d’oeuvre, and live music. Proceeds benefit the Naked Heart Foundation. 611 Fifth Ave., nr. 51st St. (212-753-4000); 6:30–8.
• Celebrate the release of Nigel Barker’s new book, The Beauty Equation, at Ted Baker. Guests have a chance to win a dinner for two with Nigel and receive a signed copy of his book with a purchase of $100 or more. 107 Grand St., nr. Mercer St. (212-343-8989); 6:30–9. E-mail firstname.lastname@example.org to RSVP.
• Stop by SITE during its fourth-anniversary party, featuring jewelry by Megan Holleran and clothing and accessories by Wonder Threads. Customers also receive complimentary food, drinks, and storewide discounts. 35-11 34th Ave., nr. 36th St., Long Island City (718-626-6030); 6–9.
• Merchandise from Matthew Ames, By Marlene Birger, Harvey Faircloth, and more is up to 80 percent off at the spring Fashionhaus sample and stock sale. Through 5/6. 58 W. 40th St., nr. Fifth Ave., ninth fl. (212-575-1500); W (9–6), Th (9–7), F (9–6).