The National Research Council has conducted 11 decadal surveys in the Earth and space sciences since 1964 and released the latest four surveys in the past 8 years. The decadal surveys are notable in their ability to sample thoroughly the research interest, aspirations, and needs of a scientific community. Through a rigorous process, a primary survey committee and thematic panels of community members construct a prioritized program of science goals and objectives and define an executable strategy for achieving them. These reports play a critical role in defining the nation's agenda in that science area for the following 10 years, and often beyond. The Space Science Decadal Surveys considers the lessons learned from previous surveys and presents options for possible changes and improvements to the process, including the statement of task, advanced preparation, organization, and execution. This report discusses valuable aspects of decadal surveys that could taken further, as well as some challenges future surveys are likely to face in searching for the richest areas of scientific endeavor, seeking community consensus of where to go next, and planning how to get there. The Space Science Decadal Surveys describes aspects in the decadal survey prioritization process, including balance in the science program and across the discipline; balance between the needs of current researchers and the development of the future workforce; and balance in mission scale - smaller, competed programs versus large strategic missions.