This study was designed to develop a psychometrically sound instrument to measure attitudes toward interprofessional collaboration in health profession students and practitioners regardless of their professions and areas of practice. Based on a review of the literature a list of 27 items was generated, 12 faculty judged the face validity of the items, and 124 health profession faculty examined the content validity of the items. The preliminary version of the instrument was administered to 1976 health profession students in three universities (Thomas Jefferson University, n = 510; Midwestern University, n = 392; and Monash University, n = 1074). Twenty items that survived the psychometric scrutiny were included in the Jefferson Scale of Attitudes Toward Interprofessional Collaboration (JeffSATIC). Two constructs of “working relationships” and “accountability” emerged from factor analysis of the JeffSATIC. Cronbach’s α coefficients for the JeffSATIC ranged from 0.84 to 0.90 in the three samples. Women obtained significantly higher JeffSATIC mean scores than men. Medical students obtained lower mean score on the JeffSATIC than most other health profession students at the same university. Psychometric support from a relatively large sample size of students in a variety of health profession programs in this multi-institutional study is encouraging which adds to the credibility of the JeffSATIC.