The complex flow conditions inherent in power plant smokestacks make accurate flow measurements challenging, which in turn limits the accuracy of hazardous emissions measurements. While stack composition measurements are assessed daily via comparison to a certified gas standard, the flue gas flow meter is only calibrated once a year via the flow relative accuracy test audit (RATA). In most cases the flow RATA is performed using an Stype pitot probe whose performance can be adversely affected by the complex flow conditions (i.e., asymmetric velocity profile and swirling flow) typical in stacks. NIST sponsored a workshop to discuss the current and future flow measurement needs with stakeholders in the electric power generation industry. The meeting included regulators, owners of stationary sources, stack testers, equipment manufacturers, national metrology institutes from other countries, flow measurement laboratories, and accreditation bodies. During the workshop participants gave presentations on several topics including accreditation, modifications to regulations that will improve flow measurement uncertainty, flow RATA accuracy for the S-type pitot probe as well as for the prism probe and spherical probe, and the accuracy of different continuous emissions measurement systems (CEMS) in stack applications. NIST gave tours and presented results from its research facilities specifically designed to improve the accuracy of stack flow measurements. At several points the workshop participants divided into small groups to discuss presentations made by invited speakers and NIST researchers. Group discussions centered around three topics including 1) Air Emission Testing Bodies (AETB), 2) Accuracy of RATA and CEMS Flow Measurement Methods, and 3) how NIST research facilities can be best used to help improve flow measurements in industrial applications. Of particular interest to the group was a non-nulling method developed by NIST that could potentially reduce RATA test time while still improving accuracy to levels on the order of 1 %. In addition, participants recommended that NIST work with the industry to validate its findings with full-scale testing of X-pattern flow monitors, non-nulling 3D probes, and the CO2 emissions mass balance on actual power plant stacks. The content of the presentations and the results of group discussion are summarized in this document.