The mining behemoth added that Williamson would "return to his mergers and acquisition specialisation at his old firm". The rest of BHP's new Group Management Committee, under new CEO Andrew Mackenzie, was also announced today, with Mackenzie saying the new team would "provide the company with the right balance of skill and experience needed to lead BHP Billiton effectively in the current environment". Healy, who specialises in complex corporate and regulatory disputes, was HSF's client relationship partner for BHP, and had previously advised the company's board on corporate governance and disputes.