Cecil Leong is Chief Executive Officer, Asia Pacific, of Mayer Brown Consulting and oversees the International Trade/WTO consulting operations in the Asia Pacific. He is part of Mayer Brown’s International Trade practice, which groups together professionals with dedicated practice areas within international trade in Asia, North America, Europe and Latin America. Cecil has extensive experience in assisting both multinational corporations and sovereign clients on various international trade matters.

Cecil has considerable experience in the area of customs advisory in Asia. He has assisted clients in matters pertaining to customs valuation, classification, post-entry audits, transfer pricing, wholesale/distribution/dealer contracts and advocacy with customs authorities, and has been involved in many important cases before customs authorities in China and Singapore. In China, he has been involved in several significant customs valuation cases over the past decade in Shanghai, Guangzhou, Huangpu, Waigaoqiao FTZ, Pudong Airport and a number of other jurisdictions. Several of his customs matters for clients were related to internal and external investigations surrounding the US Foreign Corrupt Practices Act (FCPA) investigations or local anti-bribery investigations. He has also handled customs, import regulatory and compliance matters in Indonesia, Laos, Myanmar, Philippines, Singapore, Thailand, Vietnam, Japan and India.

Cecil has assisted a number of multinational corporations in optimising their regional supply chains with a focus on Free Trade Agreements (FTAs), including the ASEAN Economic Community (AEC), Regional Comprehensive Economic Partnership (RCEP) Agreement and Trans-Pacific Partnership (TPP) Agreement. He is part of advisory consortiums with leading technology and supply chain solution providers to governments, working to enhance trade facilitation, supply chain efficiency and self-compliance in customs and international trade.

Cecil has also led foreign business delegations to look at business opportunities in Asian markets. He is actively engaged in Myanmar where he has brought together foreign investors and leading local businesses to undertake joint ventures in the areas of infrastructure development, banking & finance, FMCG, transportation, property and hospitality investments.

Chambers Global and Chambers Asia Pacific have ranked Cecil in Band 1 for International Trade/WTO in 2013 and 2014.

Before joining Mayer Brown, Cecil headed a consulting subsidiary of another international law firm for nine years. He was, prior to that, with a prominent law firm as part of its international trade group based in Singapore. He started his professional career with the Singapore government in ASEAN Free Trade Area negotiations, bilateral economic affairs with the US, Canada and Mexico and trade in services at the WTO. Cecil has a combined total of 17 years of experience on international trade and WTO matters, 14 of which were with international law firms.

For the last 10 years, Cecil has been the Chair of the Singapore Committee to the ASEAN-Japan Business Meeting (AJBM), which will see its 40th meeting in 2015 in Singapore. Cecil is also a member of the UN ESCAP Business Advisory Council, which is headquartered in Bangkok, Thailand.

Mayer Brown Consulting (Singapore) Pte. Ltd. provides customs and trade advisory and consultancy services, not legal services.

Spoken Languages

  • English
  • Mandarin
  • Thai


Stanford University, MA, International Policy

California State University, BA, Political Science (summa cum laude)

  • Band 1, International Trade/WTO: Consultants, Asia Pacific – Chambers Global (2018, 2019)
  • Band 1, International Trade/WTO: Consultants, Asia Pacific – Chambers Asia Pacific (2015-2019)
  • A client highlights his "ability to draw up scenarios and comments to counter objections, and relevant contacts in the government," as well as being "detailed with his submissions." – Chambers Asia-Pacific 2019