Knowlton (pictured) joins from GBST, a financial services tech firm, and will be responsible for business operations, technology and business change functions.
He has more than 20 years of experience in digital technology and leadership roles, including six years at Macquarie Bank in Australia and eight years as chief information officer for AXA UK.
Mark Duckworth, chief executive officer at Openwork, said Knowlton’s “vast experience” would be “fundamental” to the firm’s long-term success.
Knowlton added: “I am delighted to be joining Openwork at such an exciting time for the business and look forward to working with colleagues across the Openwork network to support its growth and development.
“I am passionate about giving advisers and their clients a market leading financial advice platform and service.”