In addition to his studies in automation technology (Dipl-Ing.), Dr. Diekmann occupied a managerial role at a medium-sized mechanical engineering company. Initially he was a sales manager at CoInvest in 1998 before being appointed as CEO in 1999. Dr. Diekmann has been a partner since 2001. He studied for an MSc in economics and wrote a thesis on the subject of risk management as part of in-service further training. As of 2005 Dr. Diekmann has been a co-shareholder of former Wunderlich & Partner GmbH (today CoInvest Corporate Finance GmbH), the initiator of the partner fund ‘Kapital für den Mittelstand’ (Capital for SMEs).