The decision to agree a one-year contract with the Centre for British Teachers (CfBT), was prompted by the resignation during the summer of the headteacher of Rams Episcopal.
While consultants have provided support for failing schools, this is believed to be the first time a company has taken on the day-to-day running of a state primary.
The CfBT is already a partner in the education action zone in the London borough of Lambeth and is one of three rival firms bidding to take over the running of Kings' Manor comprehensive in Guildford, Surrey (see above).
The new headteacher at Rams, Marianne Harris, is employed by the CfBT and will be in post for at least a year.
Hackney's education committee will next week consider a Pounds 65,000 improvement package, much of which will pay for CfBT's services.
The Church of England school is to be run by CfBT in partnership with the chief education officer, Elizabeth Reid, and the London diocesan board of education.
The move by Hackney is in response to pressure from the Government's standards and effectiveness unit.
Ministers are looking for substantial improvements in schools that have been on the failing list for more than two years.
Rams Episcopal was one of the 18 schools "named and shamed" by Stephen Byers in the first weeks of the new Government.
The school has 300 pupils and management weaknesses were identified when it was inspected by the Office for Standards in Education in March 1995.