For the second time in 16 years, Newbury Street will be closed to traffic tonight as Boston celebrates Fashion's Night Out. The fourth annual event begins at the center stage at Exeter and Newbury streets at 6 p.m. Here's a quick guide to tonight's party:

• See Patch blogger Donna Rheaume's fantastic, comprehensive preview of the evening, including tips on the best places to be.
• Check out what The Pruduential shops have in store tonight, including special sales. 
• Copley Place will play host to an evening of high end fashion shows from 6 to 9 p.m. This event is free to all.
• Have one of Sweet's Fashion's Night Out special cupcakes. 
• See photos of Fashion's Night Out last year. 

Other things to know about Fashion's Night Out:

• More than 100 retailers in the Back Bay will offer cocktails, giveaways, makeup consultations, gifts with purchase, parties, samples and much more.  
• Nineteen countries will take part in today's celebration. 
• Herb Chambers will display up to 80 luxury cars along Newbury Street, including cars from his personal collection: a Bugatti Veyron, a Ferrari Daytona Spyder and a McLaren F1.
• The work of Boston artists will be on display. 
• The event will feature Boston designers, including Britt Eldridge, the owner of Britt Ryan on Newbury Street.