The RAND Corporation will announce today that Michael D. Rich, a member of the think tank’s senior leadership team for two decades, has been selected as its new president and chief executive officer.

Rich follows James A. Thomson, who has led RAND since 1989 and announced his decision to step down in April 2011.

RAND’s Board of Trustees selected Rich after an extensive search process with the assistance of executive search firm Spencer Stuart.

“Michael Rich emerged from an exceptional group of candidates as the unanimous choice of our search committee,” said Paul H. Kaminski, chairman of the RAND Board of Trustees, in a statement. “From that impressive group, Michael’s deep understanding of RAND, his relationship-building skills and his vision for the future led us to conclude he is the best person to lead RAND going forward.”

Rich joined RAND as a summer associate in 1975 and a year later as a member of the institution’s research team upon graduating from UCLA’s law school.

As RAND’s second ranking officer since 1993, Rich has led a number of the think tank’s initiatives including expanding operations in the Middle East such as the RAND Qatar Policy Institute, securing the land for RAND’s current Santa Monica headquarters and overseeing RAND’s eight research units.

“I believe strongly in the proposition that rigorous and objective analysis leads to more effective policies,” Rich said.

Rich will take office on Nov. 1, 2011.