The National Research Council (NRC) has been conducting decadal surveys in the Earth and space sciences since 1964, and released the latest five surveys in the past 5 years, four of which were only completed in the past 3 years. Lessons Learned in Decadal Planning in Space Science is the summary of a workshop held in response to unforeseen challenges that arose in the implementation of the recommendations of the decadal surveys. This report takes a closer look at the decade survey process and how to improve this essential tool for strategic planning in the Earth and space sciences.