Anita Marsland, director of social services at Knowsley MBC, has been appointed chief executive of the newly formed Knowsley Primary Care Trust. Ms Marsland will do the two jobs simultaneously.
Ms Marsland's role will be to build on the relationship between the council and the health service in Knowsley.
She said: 'This is absolutely the right thing for the borough, providing an opportunity to build on our excellent track record of partnership working. Most people are not concerned about who provides the service, they simply expect to receive one that is good quality.'