The authors designed the sensitivity to interpersonal treatment (SIT) scale to assess how strongly individuals react to the interpersonal interactions in their workplaces. Questionnaire responses from 563 working undergraduates and 446 working adults provided data for this study. Details on the development of the new scale are provided along with initial evidence for its validity. Results indicated that the SIT is an internally consistent scale composed of two factors: self-treatment and other-treatment. Suggestions for future research that will develop a further understanding of SIT in the workplace are discussed.