Siris, a private equity firm focused on investing and driving value creation in technology and telecommunications companies, has hired Bret Griess as an executive partner. Mr. Griess will work to identify, validate and execute on Siris investments and drive performance across the Siris portfolio.

Bret Griess previously served as president and CEO of CSG Systems, a provider of revenue management and cloud payment services. In addition, Griess serves on the board of directors of Nebraska Methodist Health System, Midland University and previously held board poisons at the Student Loan Finance Corp and CSG Systems.

“Bret’s extensive experience in the technology space – combined with his commitment to turning ideas into impact – will be beneficial for Siris,” said Frank Baker, managing partner at Siris. “We expect Bret’s success in creating value-added, cloud-based business solutions will help our portfolio companies achieve their goals. We look forward to having Bret on board.”