In recent years, dedicated revenues to the Highway Trust Fund have been eroding, resulting in fewer resources to fund surface transportation projects and requiring, between 2008 and 2014, transfers of over $50 billion in general revenues. This book reviews how Highway Trust Fund monies are being used to help ensure that sound choices and investment decisions about future funding are made. The book examines what is known about the types of projects, activities, and federal administrative functions and expenses supported by the Department of Transportation (DOT) using Highway Trust Fund monies in fiscal year 2013.