This document, Cost Estimating and Assessment Guide: Best Practices for Developing and Managing Capital Program Costs (GAO-09-3SP), dated March 2009, is intended to help agencies produce well-documented, comprehensive, accurate, and credible estimates. multi-step process for developing high-quality, trustworthy cost estimates; explains how to manage program costs once a contract has been awarded; and presents 48 case studies, drawn from GAO published audits, that illustrate typical pitfalls and successes in cost estimating. The guide stresses both sound cost estimating and earned value management (EVM), a project management tool that compares completed work to expected outcomes, in setting realistic program baselines and managing risk. In future audits, GAO plans to use the Cost Estimating and Assessment Guide to assess the accuracy of agencies' cost estimates and determine whether programs are on schedule.