Tri-borough is a project between three councils in west London, England to combine service provision.
In February 2011 the chief executives of the three local authorities published a report entitled Bold Ideas for Challenging Times.
[2] This set out the plan to share services, combine back office and management costs, and gave a projected saving of £33.4m.
Under the plan the councils would remain legally distinct entities responsible for service specification and delivery.
This has included creating a joint chief executive for Hammersmith and Fulham, and Kensington and Chelsea and a single treasury and pensions team.