PPPs are but one "tool in the tool box" of project delivery mechanisms. However, given that Federal and State fuel taxes continue their long decline in the dollar value of projects they can support, PPPs will play an increasingly important role in delivery our largest and most complex transportation projects. The combination of federal support and private sector interest have strengthened the hand of state and local government officials willing to embrace the PPP project delivery tool. The continued careful and prudent use of this tool by the States should provide great benefits to the public in the years to come.