National Aeronautics and Space Administration (NASA). April 2010. Version 1.0. 128 p. The purpose of this handbook is to provide guidance for implementing the risk-informed decision making (RIDM) requirements of NASA Procedural Requirements (NPR) document NPR 8000.4A, Agency Risk Management Procedural Requirements, with a specific focus on programs and projects in the Formulation phase, and applying to each level of the NASA organizational hierarchy as requirements flow down. Appendix A provides a cross-reference between the RIDM-related requirements in NPR 8000.4A and the sections of this handbook for which guidance is provided