Federal Financial Assistance Management Improvement Act of 2012 - Requires the Director of the Office of Management and Budget (OMB) to direct, coordinate, and assist federal agencies in implementing: (1) a common application and reporting system and uniform administrative rules for federal financial assistance programs; and (2) an interagency process for addressing ways to streamline and simplify federal financial assistance administrative procedures and reporting requirements for state and local governments and nonprofit organizations (non-federal entities), improved interagency and intergovernmental coordination of information collection and data sharing, and improvements in the timeliness, completeness, and quality of information received by agencies from recipients of federal financial assistance. Authorizes the Director to exempt any federal agency or federal financial assistance program from the requirements of this Act if the Director determines that the agency does not have a significant number of federal financial assistance programs.