The Surface Reference Data Center (SRDC) was established in 1986 at the National Climatic Data Center, and was transferred to the Environmental Verification and Analysis Center (EVAC) at the University of Oklahoma in 1998. SRDC is tasked with producing gridded precipitation estimates for verification in support of the Global Precipitation Climatology Experiment (GPCP). These verification estimates are in the form of reference grid boxes. A reference box includes not only an average rainfall value, but the error introduced by averaging the point gauge data within the box. Additional information is being developed for each box, such as topographic and climatological descriptions. A variety of data sources are used to produce these products, including the Comprehensive Pacific Rainfall Database (PACRAIN) and the Oklahoma Mesonet. A new database management system (DBMS) and web interface are being implemented to enhance access to SRDC products and data. In addition to producing validation products, SRDC conducts research into new validation techniques. For more information and access to current products and data visit the SRDC web site at http://www.evac.ou.edu/srdc.