Mark Adelson, who most recently served as a senior research fellow at Standard & Poor's, has left the firm to pursue other interests.
Adelson, who joined the rating agency in May 2008, was originally hired as the firm's chief credit officer and was instrumental in strengthening S&P's criteria process.
During his stint, Adelson oversaw the development of ratings comparability across sectors and geography, which included the agency's structured finance methodology.
He was named senior research fellow in December 2011 after a reorganization that saw David Jacob, who was then global head of structured finance, leaving the firm. Jacob joined the firm right after Adelson in August 2008.
Prior to S&P, Jacob and Adelson formed Adelson & Jacob Consulting after they had left Nomura Securities. The firm offered securitization advice until right before Adelson started at S&P.
At Nomura, Adelson was head of structured finance research. Prior to his stint at the bank, Adelson was in Moody's Investors Service for nine years.