This paper aims to investigate how bank governance (board size, board composition, ownership structure) affects performance (ROA), by considering the mediating role of risk governance (presence of a risk committee, the number of meetings of the risk committee in one year, the risk committee size, the percentage of independent directors in the risk committee, and the presence of a chief risk officer). A sample of 31 Italian listed banks is examined over a ten-year period (2008-2017), in order to delineate the changes in corporate governance structure and to catch the effects of the current national and European regulations followed to the financial crisis. Hypotheses are tested by applying a mediation analysis according to the causal steps procedure. The main findings suggest that risk governance fully mediates the corporate governance-bank performance relationship. Specifically, we find that the board size is positively related to the presence of a risk committee and to the number of meetings. The percentage of independent directors on board is positively related to the percentage of independent directors in the risky committee and, in turn, has a positive effect on performance. Finally, the presence of institutional owners is positively related to the presence of a chief risk officer and, thus, to bank performance. Summing up, banks with wider and more heterogeneous boards of directors have better risk management-related corporate governance mechanisms and reach higher performance levels.