There is limited research applying the four sources of self-efficacy (Bandura, 1997) to global academic self-efficacy. This qualitative study examined the sources of global academic self-efficacy in a sample of academically high-achieving females who developed disordered eating. Semistructured interviews were conducted with 14 participants to gain an understanding of how they decided that they were or were not academically excellent before the onset of their disordered eating. The findings reveal data on the wide range of sources identified by these high-achieving females and on issues that negatively influenced how they integrated the sources into a global concept of their academic self-efficacy. Teachers should be mindful of providing information from mastery experiences, vicarious experiences, and persuasion sources to high-achieving girls so that the girls maintain a high global academic self-efficacy.