The Federal Housing Finance Agency has proposed a thoughtful path to creating a single security for Fannie Mae and Freddie Mac, using the Common Securitization infrastructure, in its August Request for Input. While the proposal would benefit from a more definitive time frame, its many strong provisions make it likely to succeed and benefit taxpayers, borrowers and lenders. A key strength of the proposal is the structural provisions which ensure that the securities backed by both entities will trade equivalently, ending the costly subsidies Freddie has been forced to pay to stay competitive. Ultimately, moving toward this single security should make the market more responsive to borrower and lender needs, boost competition, increase the availability of mortgage credit and potentially help pave the way for GSE reform.