How does one securitize a pool of mortgages, especially subprime mortgages? What is the process from origination of the loan or mortgage to the selling of debt instruments backed by a pool of those mortgages? What problems creep up in this process, and what are the mechanisms in place to mitigate those problems? Understanding the Securitization of Subprime Mortgage Credit seeks to answer all of these questions. It provides an overview of the market and some of the key players, and provides an extensive discussion of the important role played by the credit rating agencies. Understanding the Securitization of Subprime Mortgage Credit provides a broad description of the securitization process and pays special attention to seven key frictions that need to be resolved. Several of these frictions involve moral hazard, adverse selection and principal-agent problems. The authors provide an overview of subprime mortgage credit with a focus on the subprime borrower and the subprime loan and discuss how predatory lending and predatory borrowing fit into the picture. Next, the authors examine subprime mortgage-backed securities and discuss the key structural features of a typical securitization. The last section examines credit rating and rating monitoring process, and the extent to which investors rely upon on credit rating agencies views.