Andrew Vollmer concentrated his practice on securities enforcement, private securities litigation and internal investigations. In addition, he advised on matters related to the SEC's administration of the federal securities laws. He returned to the firm in 2009 after serving as Deputy General Counsel at the Securities and Exchange Commission and retired from WilmerHale in 2013.

As Deputy General Counsel, Mr. Vollmer advised the Commission on matters such as enforcement actions, rulemakings, appellate briefs and adjudications. He also served briefly as Acting General Counsel. During his tenure at the SEC, Mr. Vollmer was involved in a variety of Commission initiatives, including the SEC's participation in several Supreme Court cases and the Commission's response to court review of SEC orders and rulemakings. He also worked on the Commission's proposal and adoption of rules addressing the brokerage activities of banks; the proposal and adoption of a rule to protect fund investors from fraudulent adviser conduct during the time of their investments; and the memoranda of understanding with the Federal Reserve and the Commodity Futures Trading Commission.

Mr. Vollmer has spoken and written frequently on securities law and related matters.