Context: The assessment of an individual's mental toughness would assist clinicians in enhancing an individual's performance, improving compliance with the rehabilitation program, and improving the individual treatment program. However, no sound measure of mental toughness exists.Objective: To develop a new measure of mental toughness, the Mental, Emotional, and Bodily Toughness Inventory (MeBTough).Design: Participants were invited to complete a 45-item questionnaire.Setting: University research laboratory. Patients or Other Participants: A total of 261 undergraduate students were recruited to complete the questionnaire.Main Outcome Measure(s): The Rasch-calibrated item difficulties, fit statistics, and persons' mental toughness ability estimates were examined for model-data fit of the MeBTough.Results: Forty-three of the 45 items had good model-data fit with acceptable fit statistics. Results indicated that the distribution of items was fittingly targeted to the people and the collapsed rating scale functioned well. The item separation index (6.31) and separation reliability statistic (.98) provided evidence that the items had good variability with a high degree of confidence in replicating placement of the items from another sample.Conclusions: Results provided support for using the new measure of mental, emotional, and bodily toughness. N The difficulty of the items had good variability along the measurement scale, meaning respondents' differences could be identified well.