17 Risks should be allocated to the party best able to manage them. Not all risks can or should be transferred because the cost of inappropriate risk transfer would be too high. Although ultimate responsibility for delivering the service remains with the public sector, private finance has delivered real risk transfer. Few private finance projects have failed, but when they have contractors and lenders have normally lost most, unless the public sector provided additional guarantees. The allocation of risk calls for an active public sector role throughout, particularly in the case of risks retained by the public sector.