Ashford will work directly with Spring Advertising clients including the Conservative Party and watchmaker Dent & Co. The Suffolk-based agency's clients also include brewer Adnams, the Private Jet Club and the Chelsea Magazine Company.
Ashford previously spent four years as research manager for European publishing house IT Europa, and has also held senior positions at East of England Tourism and the Suffolk Development Agency.
Clegg said: "His tremendous knowledge adds a new dimension to Spring's work, providing sound evidence for strategic marketing and creative work.
"George is fanatical about the benefits of research and will be responsible for giving Spring's clients the information to really help their businesses grow."
Ashford said: "As well as providing background research for Spring's projects, I'll be providing research on a stand-alone basis, adding an extra dimension to Spring's work and ensuring all projects are based on sound evidence."