This post by Dan Galorath (number seven in a series) provides expert advice on the process of estimate validation and review. By this point, Galorath explains, you may feel that your estimate is good – and that may be true to a point. However, your estimate isn’t good enough: there may be potential errors that have not been caught. Making sure to perform a validation and review of the estimate can make a big difference in the future of the project. Galorath explains that the estimate validation and review process shouldn’t be done by the same person (or persons) who created the estimate in the first place. This level of objective review is important for the evaluation. He goes on to explain what should happen during the review as well, and why it’s valuable to make sure the proper time is spent in the review process: When reviewing an estimate you must assess the assumptions made during the estimation process. Make sure that the adopted ground rules are consistently applied throughout the estimate. Below-the-line costs and the risk associated with extraordinary requirements may have been underestimated or overlooked, while productivity estimates may have been overstated. The slippery slope of requirements creep may have created more uncertainty than was accounted for in the original estimate. A rigorous validation process will expose faulty assumptions, unreliable data and estimator bias, providing a clearer understanding of the risks inherent in your projections. Having isolated problems at their source, you can take steps to contain the risks associated with them, and you will have a more realistic picture of what your project will actually require to succeed. While there is some pushback whenever the term “formal validation”, the truth is that a formal validation can catch errors that would otherwise make it through in the estimate, which can have much worse consequence than simply spending some extra upfront time.