The U.S. has spent almost $43 billion to develop, assemble, and operate the International Space Station (ISS) over the past two decades. The NASA Authorization Act of 2010 required NASA to enter into a cooperative agreement with a not-for-profit entity to manage the ISS National Laboratory and in 2011 did so with the Center for the Advancement of Science in Space (CASIS). CASIS is charged with maximizing use of the ISS for scientific research by executing several required activities. Recently, questions have arisen about the progress being made to implement the required activities and the impact it has had on ISS’s return on the investment. This book assesses the extent to which CASIS has implemented the required management activities; and NASA and CASIS measure and assess CASIS’s performance. Furthermore, this book assesses the extent to which NASA has ensured essential spare parts are available and ISS structures and hardware are sound for continued ISS utilization through 2020.