For non-Japanese clients, Ken advises on such matters as tender offer and other acquisition of Japanese stock, insider trading and other trading regulations, shareholder rights and other corporate governance issues, disclosure on shareholding in listed stock, fund raising for private equity funds in Japan, investment in venture companies and IPO by subsidiaries or investee companies.

For Japanese clients (including Japanese subsidiaries of non-Japanese clients), he advises on such matters as corporate governance, disclosure and other stock exchange rules, insider trading and other securities regulations, and regulations of brokerage and investment advisory businesses, and also advises on such transactions as tender offer and share or asset acquisition, capital tie-up and business alliance, joint venture, and divestiture.

Ken is a member of the Disclosure Working Group of the Financial System Council of the Financial Services Agency of Japan (FSA), and a member of Advisory Group to the Investor and Other Stakeholders Working Group of the International Forum of Independent Audit Regulators (IFIAR).

Ken was a member of the Committee on Auditing Standards, the Business Accounting Council of the FSA, and had participated in the discussions toward adopting the Standard to Address Risk of Fraud in the Audit in March 2013. In late 2015, he participated in the discussion, as Counselor of FSA, at the investigation panel, and provided the Certified Public Accountants and Auditing Oversight Board of Japan (CPAAOB) with a report on certain auditing issues in connection with accounting scandals in Japan.

 In May 2016, he formed a new Accounting and Auditing System Research Subcommittee, The Dai-ichi Tokyo Bar Association, and has been acting as Chair of such Sub-Committee since then. Previously, Ken had served as Chair of the Financial Instruments and Exchange Act Research Subcommittee, The Dai-Ichi Tokyo Bar Association (2004-2011).

He had served as Kansayaku corporate auditor of East Nippon Expressway Company Limited, one of the major  privatized expressway operating companies in Japan (2010 to 2013).

Ken is a member of the American Bar Association (Business Law Section), and also a member of the International Corporate Governance Network (ICGN).

Locally, Ken is a member of Keizai Doyuukai (Japan Association of Corporate Executive), and since 2007 has actively been involved in the policy discussions at various committees, including the Risk Management Task Force (Member, 2009), Finance and Capital Market Committee (Vice Chair, 2011), Judicial System Reform Project Team (Member, 2013), and Employment and Labor Market Committees (Vice Chair, 2007). He is also a member of the Japan Corporate Governance Network. 

Ken Kiyohara often speaks at seminars locally in Japan, and participates in an international conference. He is also interviewed and quoted from time to time in the Japanese and English media (including Nikkei, the Financial Times, Reuters and Dealreporter) on topical issues such as corporate governance, shareholder activism, insider trading, securities regulations and other capital market related matters. Ken has written on such topics as M&A, tender offer regulations, protection of minority shareholders, corporate governance, disclosure reform, accounting fraud and auditing, and insider trading. Additionally, he contributed approximately 30 articles to "Crossroads" (Juujiro), the daily column in the Nikkei evening edition, on various aspects of corporate governance and disclosure issues during 2007 to 2013.