¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬¬The purpose of this study is to identify and structure challenges of measuringperformance of the Sales and Operations Planning (S&OP) process. A multiple case study methodology was applied. Qualitative data was collected via 22 structured interviews with managers from six case companies in various industries. A process oriented framework was proposed by structuring the challenges based on two key areas of process performance (effectiveness and efficiency) and different maturity levels of the process. A major challenge for all the cases,regardless of their maturity level, relates to defining of cross-functional trade-offs measures. Another major challenge was alignment of measures with business strategy and reward system. Additional common challenges for the different maturity levels were also found. While confirming some challenges from previous research, this study also finds new challenges, especially for more mature levels. Examples are standardization to support unbiased decision making, but also customization of measures for various organizational levels, and visualization of findings from the measurement to facilitate analysis. However, future research must validate and extend the results in other industries. The results offer challenges from a process oriented view and can serve as insights for managers when designing and implementing the S&OP process measures, or advancing from one maturity level to another. This research enhances understanding of the challenges to measure the S&OP process performance and adds to the S&OP literature and performance measurement literature.