Right now, the service is only available in the Metro Phoenix area, serving the cities of Chandler, Gilbert, Mesa, and Tempe. The self-driving Chrysler Pacifica Hybrid minivans can accommodate up to three adults and one child per trip, and at first will be limited to what Waymo describes as "early riders".
Early riders -- which numbers in the hundreds -- were previously part of Waymo's research program to test the feasibility of Waymo One and helped worked out initial bugs in the service. However, Waymo hopes to open the service up to more to the public in the future and we'll also see the list of supported cities grow.
And for those that might be apprehensive about a fully-automated vehicle shuttling them around from place to place, Waymo addresses these concerns in a blog post:
Our early riders have shown us that the first time people take a self-driving ride, they have questions. That’s why we’ve put support literally front and center in our cars. With the tap of a button on our in-car console and screens, or through the Waymo app, riders can connect instantly to a rider support agent to ask questions like, “What if I want to change my destination during the trip?”.
If you're familiar with Uber or Lyft, hailing a ride with Waymo One is very similar. First, you'll have to confirm your pickup location using the Waymo One app, then you'll enter your final destination. Finally, you'll press the "Request Ride" button to send a vehicle to your current location.
In case you were wondering, Waymo One vehicles will operate in fully autonomous mode for rides, but will be "supervised" by a human at all times in case of emergency. Waymo did not provide any details on when the human babysitter will be eliminated.