This Feasibility Study to Develop a Methodology to Monitor the Impact of Changes in Competitive Food Policies had two main goals: (1) Design and test a plan for collecting and analyzing data about competitive food policies and all foods offered and served to students at school; and (2) Provide a methodology for assessing the impact of changes in competitive food policies on the nutritional quality of all foods served at school. To achieve the first goal, data collection instruments and procedures were developed and data were collected from three schools during May of 2003. The study collected data about the availability of competitive foods (locations and time periods), school nutrition policies, and financial arrangements related to the availability of competitive foods, and descriptions of all food and beverage items offered and served to students during the school day. Data about competitive foods were entered in a nutrient analysis system, and food group and nutrient analyses of these items were conducted. Lessons learned from the data collection and analyses were then used to address the second goal of the study. Recommendations include a description of overall design considerations, methodological and operational issues involved in collecting information about competitive food policies and competitive foods offered and served, alternative outcome measures, and methods of analysis. Appended are: (1) Instrument Design and Data Quality Issues; (2) Validation Study Findings; (3) Nutrient Database Issues; (4) Reimbursable Meal Menus; (5) Competitive Foods Available During the School Day; (6) Competitive Foods Available Outside the School Day; and (7) Instruments. [Report submitted to the Office of Analysis, Nutrition and Evaluation.]