Your next car ride down Market Street might be your last. Come January 29 the busiest sections of San Francisco’s busiest street will be closed to most civilian auto traffic—possibly forever.

City Hall touts this part of its ongoing, $604-million plan to improve the city’s centerpiece thoroughfare to eliminate traffic deaths and maximize public transit.

The plan seemed popular with most of the public when proposed last year, although a few critics fretted that the new rules could intensify gridlock on parallel streets. Nevertheless, the SF Municipal Transportation Agency board approved the plan unanimously in October.

Here’s what this means in practical terms for SF commuters:

The street will not eliminate vehicle traffic altogether: Muni buses, bikes, emergency vehicles, paratransit, vehicles with commercial plates, and actual taxis with city-issued medallions (but not Lyft or Uber cars) will continue using Market as they always have. Other private vehicles will still be able to use Market Street as a cross street.

The prohibitions extend in the eastbound lanes between Tenth Street and Main Street, and westbound between Steuart Street and Van Ness Avenue.

The city will add new transit-only lanes to some parts of the street and change some other lanes that previously allowed other transit operators to be Muni exclusive starting this month.

SFMTA hopes that these changes will cut down or eliminate traffic deaths on Market Street; of the ten worst intersections in the city for collisions with bikes or pedestrians, five of them are on Market Street.

Related SF votes to ban cars from Market Street

The closure is also a bid to improve Muni performance, as Market Street has some 200 buses per hour at the busiest times of the day, but these busy lines often end up stalled in traffic.

Future Market Street improvements set to begin construction this year include widening the sidewalks downtown and creating the likes of plazas, performance spaces, and bike facilities along the 2.2 mile stretch singled out in the Better Market Street plan.

Among American cities, only New York City has attempted any similar experiment recently, closing a section of 14th Street in Manhattan to all but bus traffic. But as Vox notes, many European cities have set up car-free zones in busy downtowns, with general success.