The appropriately named agency beat off three other consultancies in a pitch for the business.
It will target central and local government to raise awareness of the environmental benefits of car clubs. In particular, it will push for more parking spaces for clubs and for users to be exempt from congestion charges.
Clubs let members hire locally parked cars for an hourly fee. They are now operating in 26 towns and cities, and rural areas. The biggest firms in the business are City Car Club and Streetcar - which currently has around 10,000 members but expects this to rise to over 20,000 by the end of the year.
Open Road will initially target central government, Transport for London, the Greater London Authority and London boroughs to raise awareness of car clubs' contribution to reducing emissions and congestion.
The agency will emphasise that a high proportion of Streetcar members give up their car or do not buy one. It will also stress that members drive less after joining the scheme and use public transport more frequently.
Open Road was set up last month by well-known figures in PA and corporate comms consultancy (PRWeek, 12 January). Its chief executive is Graham McMillan, former Fishburn Hedges head of PA.
This week, Open Road was accepted as a member of the Association of Professional Political Consultants. This takes the APPC's membership to 39.