The literature currently lacks a psychometrically valid and reliable assessment tool that adequately measures the fat talk construct. This research aimed to use qualitative data gathered from young adult women to guide development of a fat talk measure. In Study 1, 14 individuals participated in fat talk themed focus groups or individual interviews. In Study 2, 257 participants completed questionnaires measuring fat talk and theoretically related (e.g., body image) and unrelated (e.g., 'academic talk') constructs. In a preliminary analysis, the newly-developed Fat Talk Questionnaire was found to be reliable and valid. In future research, the Fat Talk Questionnaire should be refined to further improve its psychometric properties.