Jeremy Parr is understood to be joining A&O from Ashursts in May. David Lee has joined A&O's public/private partnerships and private finance initiative department as a partner.
Parr specialises in legal issues surrounding mergers and acquisitions, particularly cross-border acquisitions, UK domestic acquisitions, de-mergers and flotations.
Richard Cranfield, A&O's head of corporate, says: "We have known Jeremy for some time.
"His capabilities and aspirations match those of A&O, and so once he joins us, Jeremy will be able to build the type of practice he wants based on his expertise, which fits well with the development of A&O's international practice."
Geoffrey Green, senior partner at Ashursts, says: "I don't like losing good people. But he will not take any clients with him."
Lee is also a key appointment for A&O. In 1997 he was appointed to the Government Treasury project taskforce, which was set up to drive through PFI deals.
Lee co-wrote the Government booklet on PFIs called Treasury Taskforce Guidance – PFI Contracts. His experience on the taskforce gives him inside knowledge of how PFI policy is devised. Before working for the Treasury, Lee was a senior project finance assistant at A&O.
Anne Baldock, A&O's head of PFI, says: "We anticipate further growth in PPP/PFI work, particularly as other countries begin to take advantage of the UK experience.