She replaces Tom Fuller, who has moved across the Atlantic to set up Mo'web's first US office.
Rowell, who has nine years' experience in the market research industry and formed her own company, in 2007, will report to managing director Herbert Hockel.
Hockel said: "In addition to the exciting and new methodologies emerging, there is a growing interest in research outside the main five European markets.
"With the help of our international panels, which have recently been extended to include Poland, Russia, Benelux and Scandinavia, we want to ensure that we stay at the forefront of new developments.
"We are very happy to announce Cathrene joining our team. In addition to her prominence in the market research network, Cathrene has the right mix of character, expertise and experience to help us build upon Mo'web's excellent track record for quality online market research."
is an international full-service online research agency, with offices in Europe, the US, Asia and Africa. It was founded in 2002.