How do we measure and verify façade energy performance? The intent is to correlate simulated design performance with the constructed reality. What are the challenges and how do we measure success? What procedures are necessary for performance verification through a commissioning process and post-occupancy monitoring for varying project types and complexity? Addressing new construction is only part of the path to net zero; deep energy retrofits of existing buildings is even more essential. Performance measurement and validation of this project type presents its own challenges. These critical issues will be discussed from the varying perspectives of the owner, consultant, and constructor, with a focus on managing expectations and delivering results.