Many climatologies for the US from 1895 onward are based on the US Historical Climate Network (USHCN). The National Climatic Data Center has embarked on a project to improve this baseline dataset with a release called the 2002 USHCN. Improvements in inhomogeniety detection and quality assurance techniques will result in major enhancements to the data quality. Topics to be discussed during the presentation include: Results in the selection of current stations to reestablish discontinued sites. The expansion of the network with the addition of recovered data for the first half of the 20th Century from the Climate Database Modernization Project. A summary of quality control tests (based upon the Global HCN QC algorithms) that have been improved to include flagging for snow observations in precipitation and better passing of extreme outliers in both temperature and precipitation. An overview of the inhomogeneity schemes and their interplay with a new evaluation technique (using the sum of the absolute diffence of anomalies) that verifies or negates proposed adjustments to the station's series.