Registration has just begun for Dîner en Blanc, the chic, pop-up outdoor dinner party that's become quite the ticket. This year's edition - the fourth - is set for Thursday, Aug. 20 at an undisclosed location.

Organizers will accommodate 4,300 guests this year.

Registration is only slightly less complicated than algebraic geometry. Phase 1 began July 8, among last year's registered members. Phase 2 will begin July 15 and will cover friends sponsored by Phase 1 members. Phase 3 will open July 20-23; lottery software will randomly select names from a waiting list, and new participants selected by lottery can register for DEB using a special code.

Potential attendees can add their name to the waiting list by 11:59 p.m. July 17.

Diner en Blanc's shtick is this: Registered guests, dressed in white, bring their own feast, table, chairs, and table setting to an appointed spot, from which they will be told the exact location. They set up en masse. Over the course of the evening, they dine amid music, entertainment and dancing.

Guests must bring:

A table, two white chairs, a white tablecloth, stemware, and dinnerware. Prizes will be awarded for best table decorations.

A picnic basket with fine food and drink. Food should be brought in reusable and/or recycled containers.

Champagne or wine. Beer and hard liquor are prohibited.

A catered picnic basket option, which can be picked up at the site, will be also available for those who do not wish to pack their own. Guests wishing to do so must reserve online through Dîner en Blanc website during the initial ticket registration. This year's official caterers are Garces Events, Di Bruno Bros. Catering and Luke Palladino Catering.

* Except the location. That's a secret till the evening of Aug. 20.