Objective: Assess validity of the ecSatter Inventory (ecSI) to measure eating competence (EC). Design: Concurrent administration of ecSI with validated measures of eating behaviors using on-line and paper-pencil formats. Setting: The on-line survey was completed by 370 participants; 462 completed the paper version. Participants: Participants included 863 adults with 832 usable surveys from respondents (mean age 36.2 [plus or minus] 13.4 years) without eating disorders, mostly female, white, educated, overweight, physically active, and food secure. Of those indicating intent to complete the on-line survey, 80.3% did so; 54% of mailed surveys were returned. Variables Measured: Eating and food behaviors compared among EC tertiles and between dichotomous EC categories; internal consistency of ecSI. Analysis: Analysis of variance, independent t tests, chi-square, factor analysis, logistic regression. Significance level was P less than 0.05. Results: Mean ecSI score was 31.1 [plus or minus] 7.5. ecSI included 4 subscales with internal reliability and content validity. Construct validity was supported by specific behavioral profiles for ecSI tertiles and ecSI dichotomized categories. Persons unsatisfied with weight were 54% less likely to be EC; unit increase in the food like index was associated with nearly 3 times greater likelihood of being EC. Conclusions and Implications: The ecSatter Inventory is a valid measure of EC and can be used for descriptive and outcome measurements. (Contains 7 tables.)