General Motors expects to have self-driving cars cruising city streets sometime in 2019.
The auto giant revealed plans to test a self-driving taxi-like service during an investor event in San Francisco on Thursday.
GM president Dan Ammann told investors that passenger safety is the biggest challenge that the company’s autonomous vehicle plans faces, saying that the “bar is very high.”
“This will be the deciding factor from when we’re ready to take the driver out of the car and deploy this technology at large scale,” Ammann said.
In 2016, GM bought self-driving car startup Cruise Automation for more than $1 billion to bolster its autonomous vehicle plans. Since then, GM has been testing self-driving cars in San Francisco, the Phoenix suburbs, and Detroit.
Get Data Sheet, Fortune’s technology newsletter.
Uber and Lyft are also testing self-driving cars, raising the potential of a face-off with GM. In September, Ford Motor and Lyft said they would partner on their own self-driving car initiative.
In corporate slides related to the investor event, GM appears to dismiss the potential competition by saying the ride-sharing market “is at very early stages.”
Investors didn’t seem thrilled with GM’s self-driving taxi push. The company’s shares fell 1.6% to $43.09 on Thursday.