Today Lyft and General Motors together kicked off a rental car program that aims to make “car ownership optional” for both passengers and drivers, Lyft president John Zimmer said during a call with press.

The initiative marks Lyft’s first public project with GM since the ride-hailing startup raised $500 million from GM in January. The two companies teased a rental program months ago, saying GM would “establish a series of national rental hubs where Lyft drivers can access short-term vehicles.” At the time, Lyft and GM also announced a second plan: to “build a network of on demand autonomous vehicles.” (Lyft’s chief competitor, Uber, is also toying with autonomous vehicles.)

It turns out that the two projects are intertwined, according to GM’s head of urban mobility, Julia Steyn. The rental program “builds infrastructure that is very critical and a very important step towards our joint work and future goal to develop an integrated on-demand network of autonomous vehicles,” said Steyn.

But when pressed to share a timeline for a self-driving car launch, both companies remained mum. “We’re working as quickly as possible to make that a reality,” Steyn said. “Again, I think, John and myself multiple times said that this partnership means that we can accelerate this offering, so both sides and both teams are working really fast on that.”

However this infrastructure may be used in the future, for now, the companies are publicly focused on getting more Lyft drivers on the road. “With this program, you don’t need to own a vehicle to be able to earn money on the platform and give rides to passengers,” said Zimmer. The program — which is launching in Chicago and coming to D.C., Baltimore, and Boston later — offers rentals for between one and eight weeks, and is priced to incentivize Lyft drivers to actively offer rides. If, say, a Chicago driver gives 65 or more rides in a single week, Lyft says the price for renting a car that week drops to $0.