The authors describe an instructional model of interdisciplinarity that aims to simultaneously develop undergraduate students' disciplinary knowledge and foster integrative skills. Two faculty members taught separate undergraduate courses in history and microbiology during which students came together at multiple points throughout the semester. During these joint sessions, the students integrated disciplinary perspectives to examine the significance of natural disasters for public health. While group assignments initially reflected minimal integrative moves, the final assignments reflected students' progress in interdisciplinary writing. The authors describe the guiding principles that informed this interdisciplinary model and present evidence of student development on integrative tasks.