Eversheds has won a three-year contract to be sole legal adviser to the National Assembly for Wales.
The firm was up against four unnamed rivals to win the prestigious contract, which involves advising on matters relating to employment, equal opportunities, health and safety, property and land-related issues, commercial law, procurement and litigation.
Eversheds will also advise when required on intellectual property and data protection issues. The work will be carried out from the Cardiff office and commanded by commercial litigation partner Peter Watkin Jones and property partner Eric Evans.
The core legal work will still be handled by its in-house team.
In a separate appointment the firm will also provide pensions-related advice to the Trustees of the Assembly Members' Pension Fund. The work will be carried out by the firm's specialist pensions unit in Cardiff, headed by partner Ian Davies.
A spokeswoman for Eversheds says that the contract represents a valuable triumph for the lawyers involved and staff who prepared the pitch were delighted with the result.
She says: “The contract was advertised in the legal press across England and Wales so there were a lot of applicants, which were then whittled down to a shortlist of four.
“The Assembly was after a firm that had a wide range of experience, as well as the resources and ability to deal with the changes the body will face.
“We have great local market knowledge combined with an international perspective, which is what they were looking for.
“As well as being the largest legal practice in Wales, the Cardiff office is rated as the leading practice. We have worked a lot with the public sector including a contract with the Welsh Development Agency for the past 10 years. This could have been a major factor in swinging the deal our way.”