Williams has specialised in M&A for more than 20 years, as well as joint ventures in the energy, resources, infrastructure and industrial sectors.
His experience includes advising a range of Asia-based clients.
He also holds a number of other roles including executive director of New Hope Corporation (ASX: NHC), vice president of the Australia Japan Business Cooperation Committee and vice chairman of the Australian Korean Business Council.
Williams also played professional rugby union for both Australia and Japan.
Herbert Smith Freehills global head of corporate, Mike Ferraro, says Williams' expertise in Japan and Korea will help boost clientele in Asia Pacific.
"Ian's considerable expertise and strong relationships with Japanese and Korean organisations in particular will bolster our client offering in Asia Pacific and build upon the firm's significant cross-border capabilities in the region," says Ferraro.
"We expect to see strong M&A activity across the Asia Pacific region in 2015, with cross border deals set to increase as a result of Australia's new Free Trade Agreements with Japan, Korea and China.
"The falling Australian dollar and lower commodity prices will also drive M&A activity and increase foreign investment into Australia."
In the most recent Thomson Reuters M&A Legal Advisor league tables, Herbert Smith Freehills' Corporate M&A practice in Asia Pacific was ranked first by both deal volume and total value of announced and completed deals in Australia and New Zealand.
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