Joel Mandelbaum joined Wall Street Systems as chief executive officer, having worked in the capacity of advisor and co-investor during the acquisition of Wall Street Systems, in January 2006. Before taking on this role, Joel was chief executive officer and principal of Financial Sciences, a software company that specializes in enterprise-wide treasury, custody and direct issuance of commercial paper.

Previously, Joel held the position of president at Thomson Market Information Services, running eight companies across a number of business lines, including securities pricing, asset-backed securities, municipal bonds, trading and electronic publishing. During that time, Joel had merger and acquisitions responsibilities for Thomson Corporation, a US$8 billion electronic publishing company.

Earlier in his career, Joel worked at Lehman Brothers as a vice president in investment banking, specializing in Public Finance, New Product Development and Special Situations. He has also acted as chief operating officer and principal of Dalcomp, Inc., a provider of financial telecommunications software and floating-rate trading software. Joel has a BSc from Massachusetts Institute of Technology. He is an active Telemark skier, cyclist and swimmer.