The department announced that Eryl Besse would join the board on 3 June as its required member with expertise in Welsh charities.
Besse, who speaks Welsh, is a solicitor with more than 30 years’ experience and was a partner at both Linklaters and Debevoise & Plimpton. She is a member of the development committee campaign board at Magdalen College School in Oxford.
Besse was appointed after the other six new commission board members because Francis Maude, the Minister for the Cabinet Office, was required to consult the Welsh government about the appointment, the Cabinet Office said.
Walter Rader, an existing board member, has been appointed deputy chief commissioner on a five-year term, and Brenda Maitland and Geraldine Donaghy were appointed as commissioners on three-year terms by the Department for Social Development.
Rader is a former chief executive of the Big Lottery Fund in Northern Ireland. Donaghy was formerly chief executive of the Confederation of Community Groups, Newry & Mourne. And Maitland was a senior HR business partner at BT Northern Ireland.
Chief commissioner Tom McGrath said: "Both Geraldine and Brenda will bring a wealth of experience and knowledge to their new roles and I am delighted to welcome them on board.
"I have worked with Walter for a number of years on the board and I look forward to continuing our close working relationship as the commission begins its biggest task to date – compulsory registration of all charities operating in Northern Ireland – later this year."