Purpose: The purpose of this paper is to describe the student learning outcomes (SLOs) for a sustainability major, evaluate faculty incorporation of the SLOs into the courses in the sustainability major curriculum and measure student performance on the SLOs from entry into the major to the senior capstone course. Design/methodology/approach: Through an iterative approach with a faculty advisory committee, SLOs were developed for the sustainability major. Curriculum mapping followed by evaluation of course syllabi were used to determine the extent to which each course addressed the SLOs. Student performance on most SLOs was measured through student assessment in an introductory and capstone course to evaluate the change in performance over time. Findings: The core courses of the sustainability major were more likely to address the SLOs of the major than that of the elective courses. Where measured, student performance on the SLOs increased from the introductory course to the capstone course. Sustainability majors participated in an average of almost ten experiential learning opportunities focused on sustainability. Originality/value: This research provides a longitudinal assessment of student learning in an undergraduate sustainability major. Because undergraduate sustainability degrees are generally new, this research can serve as a base upon which to continue to improve sustainability curriculum design.