Waymo, Alphabet’s self-driving car unit, is preparing to launch the first commercial ride-sharing service powered by self-driving vehicles with no human “safety” drivers as soon as this fall, according to two people briefed about the plan. (See this article about Waymo’s recent Phoenix experience.) Yet as it takes this crucial step, Waymo is grappling with discord in its upper ranks that has hurt morale in some areas.

Dmitri Dolgov, who runs software programming for Waymo and is a member of the unit’s old guard, has privately criticized the management of CEO John Krafcik, who was appointed in the fall of 2015, according to three people who have spoken to him or heard his comments. Among his complaints: Mr. Krafcik’s lack of technical knowledge about self-driving systems and how that affects bigger decisions on how to launch a commercial service.