TriNet Group Inc. (NYSE: TNET), the fourth-largest US professional employer organization, appointed Brady Mickelsen as senior VP, chief legal officer and secretary. Mickelsen succeeds Gregory Hammond; who will retire on June 21 after nearly 20 years with the firm.

Mickelsen most recently was a partner in the Silicon Valley office of global law firm White & Case LLP. Prior to White & Case, he was VP, associate general counsel and assistant secretary at Oracle Corporation.

Hammond joined TriNet in 1997. He implemented programs for scalable growth, a legal process, a culture of compliance and quality-assurance, and played a leading role in TriNet’s initial public offering, according to the firm.

“Greg Hammond’s visionary work and expertise were crucial to TriNet’s success,” said President and CEO Burton Goldfield. “His contributions helped shape TriNet into the HR partner of choice for America’s leading small and mid-sized businesses. It is my pleasure to welcome Brady Mickelsen to TriNet’s executive team. His strong background in managing corporate governance and compliance programs, supporting operational teams and advising on business transactions will be an incredible asset for TriNet and our clients as we continue to grow.”

“Working for TriNet was the highlight of my professional career and a true labor of love,” Hammond said. “I am honored by my association with TriNet and the many dedicated individuals with whom I have had the pleasure of working.”