Historically, much of the banking regulation that was put in place was designed to reduce systemic risk. In many countries capital regulation in the form of the Basel agreements is currently one of the most important measures to reduce systemic risk. In recent years there has been considerable growth in the transfer of credit risk across and between sectors of the financial system. In particular there is evidence that risk has been transfered from the banking sector to the insurance sector. One argument is that this is desirable and simply reflects diversification opportunities. Another is that it represents regulatory arbitrage and the concentration of risk that may result from this could increase systemic risk. This paper shows that both scenarios are possible depending on whether markets and contracts are complete or incomplete