Based in London, Hildebrand will report to Laurence Fink, BlackRock's chairman and CEO, and will oversee the firm's largest institutional client relationships in Europe, the Middle East, Africa and Asia Pacific from October, the U.S. fund manager said.

"He will contribute a unique perspective on global markets and economic trends to BlackRock's investment teams and also represent the firm to senior government officials and regulators across EMEA and Asia Pacific," BlackRock said in a statement.

Hildebrand resigned from the Swiss National Bank (SNB) after he failed to prove he had not been involved in lucrative currency trades by his wife, Kashya, just weeks before he oversaw the introduction of a cap on the Swiss franc's value.

The former Moore Capital hedge fund manager, who controlled his own portfolio while at the SNB, was later found by not to have broken the central bank's old rules, which were tightened up after the scandal.

He joined the SNB in 2003, rising to chairman in 2010, and won praise for helping to orchestrate the 2008 bailout of UBS (UBSN.VX), which prompted tougher Swiss banking regulations.

Supremely well connected among policymakers and bankers, he was appointed vice chairman of the Financial Stability Board, the regulatory task force for the Group of 20 economies, just months before the scandal broke. He also relinquished that post upon leaving the SNB.

Since March, he has been a visiting fellow at the Blavatnik School of Government at Oxford University - where he studied at Lincoln College and received his doctorate in international relations in 1994.

"ENVIABLE REPUTATION"

Hildebrand made his first public appearance in Switzerland since the scandal last week at an economic conference, where he discussed the euro zone crisis and the urgent need to quickly stabilize the European banking system.

Meanwhile, Christoph Blocher, the right-wing politician who helped force Hildebrand's resignation, is fighting to avoid prosecution over his role in leaking the private bank information that exposed Hildebrand's wife's currency trades.

New York-based BlackRock, founded more than 20 years ago as a one-room bond investment firm, has become the world's largest publicly traded asset manager through a series of acquisitions, led by Fink.

It sidestepped the toxic assets that laid low many of its rivals in the financial crisis, and now has around $3.7 trillion of assets under management.

"BlackRock's deep investment expertise and superlative risk management, together with its commitment to outstanding client service, have a deserved and enviable reputation in the world," Hildebrand said in the BlackRock statement.

Hildebrand's latest move marks a return to the private sector, where he began his career before becoming a central banker. Before the SNB, Hildebrand worked as chief investment officer at Swiss banks Union Bancaire Privee in Geneva and Vontobel in Zurich. Prior to that he was a partner at U.S. hedge fund Moore Capital Management in London and New York.

Five years ago, Allianz AG's (ALVG.DE) Pacific Investment Management Co (Pimco) signed up former U.S. Federal Reserve chairman Alan Greenspan as a consultant on economic issues.

Shares in BlackRock, valued at $30 billion, have slipped 3 percent so far this year, underperforming a 3 percent gain on the Dow Jones industrial average .DJI.

(Reporting by Stephen Mangan, additional reporting by Jochelle Mendonca and Emma Thomasson; Writing by Ian Geoghegan; Editing by Himani Sarkar, Neil Fullick and Jane Merriman)

• A Permanent Economic Emergency