Mr. Mendel passed the traineeship program at Bayerische Vereinsbank and graduated as „Bankkaufmann“. At the university in Augsburg he specialized in finance, audit , controlling and operation research. After the master degree in economics he joined again Bayerische Vereinsbank and worked in the risk management, corporate banking and corporate finance. After heading the corporate finance division he became responsible for the group risk management.

Before he became a member of the group management board of HVB-Group he joined as CRO the board of Bank Austria. In his function as CEO of Österreichische Volksbank AG from 2008 until June 2019 he was responsible for the restructuring of the banking group.