Turning Avoidable Guidelines Into Sensible Requirements -- Credible Space Cost Estimating Policy

In the last five years NASA has experienced a renaissance in cost estimating. The small crew of remaining estimators at the Agency started an effort to rebuild the cost estimating capability at all of the Centers, including NASA Headquarters. This involved growing the number of trained cost estimators, educating cost estimating customers and providing guidance on the discipline of cost estimating at NASA. Without these three components credible cost estimates within NASA would not be possible. Five years later, with a robust cadre of trained estimators, how has the cost estimating message been delivered to customers? How have all of the Centers come to agreement on the guidance for their estimates, providing the consistency that leads to the credibility of recent NASA cost estimates? One of the most visible tools that has increased estimating credibility at NASA is the Cost Estimating Handbook (CEH). First published in 2002 and now in revision for the third edition, the NASA CEH has captured inputs from all of the NASA Centers and found consensus on how cost estimates should be conducted at NASA. This paper focuses on the methods and tools that have taken the initial "avoidable guidelines" originally found at NASA and transformed them into sensible cost estimating requirements that the NASA cost estimating community can follow. This paper will discuss how communication between the Centers led to consistency in requirements and cost estimates, resulting in credible cost estimates at NASA.