Sandia National Laboratories is facilitating a collaborative group of photovoltaic (PV) professionals (PV Performance Modeling Collaborative or PVPMC).  This group is interested in improving the accuracy and technical rigor of PV performance models and analyses.  Such models are used to evaluate current performance (performance index) and determine the future value of PV generation projects (expressed as the predicted energy yield) and, by extension, influence how PV projects and technologies are perceived by the financial community in terms of investment risk.  Greater confidence in the accuracy of performance models will lead to lower financing costs and an increase in the number of projects that are built.  The PVPMC provides a collaborative venue for working towards these goals.