Think of restaurant rules that have been relaxed over the years:

* Sunday blue laws, closing bars.

* Mandatory jackets for men at many fine-dining restaurants.

Add to that: the ability to make a reservation at the Standard Tap.

The Northern Liberties landmark, which helped launch the city's gastropub movement when it opened 14 years ago, has gone to OpenTable to allow bookings for lunch and dinner in the second-floor dining room and porch. Both bars and the first floor are still first come, first served.

Every restaurateur wrestles with reservations. Accept them, and prepare for inevitable no-shows. Don't accept them, and cringe as customers hear "a 45-minute wait" during busy nights and go elsewhere.

The Tap's seating system has improved. For many of the pub's early years, would-be patrons had to patrol the dining room and pounce on tables as they opened. Then, around the opening of the second floor, a hostess was appointed to keep a list.

"We liked the open seating and that democratic feeling," co-owner William Reed told me. "We felt that even though we had high aspirations [for food and service], we always liked the feel of the place to be casual."

By casual, as in, no reservations.

"Then we realized after 14 years that we're saying no to people a lot," he said, acknowledging that the mind-set was "completely out of date for us."

He discovered that the Tap did allow reservations - but only for parties of 20 and more. "I asked, 'Why are we doing that?' We were kicking ourselves for keeping an old idea alive longer."

For every online reservation received via the website now through Christmas Day, Standard Tap will donate $2 to  Philabundance; you must type the word "Philabundance" in the Special Requests field.