In this study, we reviewed pharmacoeconomic guidelines from the United Kingdom, Spain, Italy, Australia, Canada, and the United States to determine areas of emerging standardization. We examined the published literature, publication guidelines of major health journals, and published and unpublished recommendations from various task forces and conferences on related topics. The review revealed several general principles for which there was consensus across guidelines. These common features included the importance of using and reporting transparent methods so that readers can easily understand what calculations are being performed on which data elements, minimizing bias, and providing justification for the methods and assumptions used. Differences were detected across guidelines on the following topics: type of pharmacoeconomic assessment, perspective, comparators and data sources, data analysis, cost analysis, future cost analysis, outcomes assessment, modeling, time horizon, discounting, disclosure, and generalizability. Evolution of economic guidelines hinges on whether the primary goal is to increase the consistency or increase the validity of economic assessments. Some balance between these two objectives is desirable.