A new study from Juniper Research forecasts that almost 20 million fully autonomous vehicles will be on the road by 2025, representing just 1 percent of all vehicles globally.

Consumer adoption of self-driving cars is projected to take off in 2021, according to the study. In the meantime, growing use of advanced driver assistance systems, such as adaptive cruise control and automated emergency braking, will likely help to psychologically prepare drivers for the arrival of autonomous vehicles, researchers noted.

The new research, Autonomous Vehicles: Adoption, Regulation & Business Models 2015-2025, finds that although the market has progressed to live trials, a clear-cut monetization strategy hasn’t yet become evident. Stakeholders are currently investigating multiple business models, with manufacturers expected to engage in product licensing, self-production or open sourcing the systems.

The U.K.-based research firm ranked Google, Volvo, Daimler, Tesla and Apple as the most promising players in the autonomous car sector. The companies were scored on a number of key factors including live trials, miles tested on the road, technology development, project scale and scope, future potential and market opportunities.

Juniper ranked Google as the No. 1 most promising player because the technology giant has been engaged in development the longest and has logged the most autonomous miles on public roads. The study acknowledged public concerns over the decision-making capabilities of autonomous vehicle technology, but researchers argued stakeholders will need to collaborate to establish system safety standards.

The report forms part of Juniper’s ongoing analysis of Connected Cars & Telematics and is now available to download from the Juniper Research website.