Several possible explanations have been suggested for this untoward state of affairs–the lack of servicer capacity to execute modifications, purported financial incentives for servicers to foreclose rather than modify, what until recently appeared to be easier execution of foreclosures relative to modifications, limits on the authority of securitization trustees, and conflicts between primary and secondary lien holders. Whatever the merits and relative weights of these various explanations, the social costs of this situation are huge. It just cannot be the case that foreclosure is preferable to modification–including reductions of principal–for a significant proportion of mortgages where the deadweight costs of foreclosure, including a distressed sale discount, are so high. While some banks and other industry participants have stepped forward to increase the rate of modifications relative to foreclosures, many have not done enough. I would hope that both servicers and ultimate holders of the mortgages will take this occasion not just to correct documentation flaws and to contest who should bear the losses of mortgages gone bad, but to invigorate the modification process.