Banks perform the essential economic task of collecting funds from net savers (such as households) and lending funds to net borrowers (such as firms). In doing so, banks transform assets with respect to size, maturity, and risk. As a result, banks are exposed to a variety of risks. This thesis consists of two parts where particular aspects of bank risk are discussed. The first part is concerned with the question how banks themselves deal with certain aspects of bank risk by using the interbank market. An important issue for bank risk and financial stability is the structure of interbank markets and thus the determinants of banks' choice of their interbank market partner. Information between banks is a crucial factor for explaining bank beh...