The Parliamentary and Health Service Ombudsman (PHSO) is creating its first-ever legal panel.
The London-based regulator, which investigates more than 3,000 complaints each year about the NHS, Government departments and other public bodies, is creating the panel for general, litigation and employment advice.
In-houser Anne Harding said: "We're looking to ensure that public money is spent economically and effectively, and we want to develop structured working relationships with providers to gain additional benefits through training and access to resources."
An invitation to tender will be made on 9 October and the process is due for completion by the end of December.
Contracts will be awarded in early January to provide services for a three-year period, with an option to extend the contract for a further two years.
PHSO received 21,397 enquiries in the financial year 2005-06 and took on 3,162 new cases for investigation. Its legal spend was £300,000.