Non-profit organizations (NPOs) are often resourcerestricted and rely on volunteers to function. As such, their human infrastructure-The social system supporting work-is different from conventional organizations, and technologies that function in a traditional organization with a stable workforce may not work in NPOs. Through an investigation of the deployment of an Electronic Health Record (EHR) system in a safety-net free clinic serving underprivileged populations, we report how the EHR system disrupted the human infrastructure-namely, the work typically enacted by volunteers. Specifically, there was a mismatch between the technological and human infrastructures leading to diminished volunteer roles, an increased workload for paid employees, and a negative impact on the quality of patient care. In turn, employees acted to reconcile the disrupted human infrastructure by creating new work roles for volunteers, re-establishing the quality of patient care, and developing workarounds for volunteers to resume their volunteer work. Finally we discuss how the commercial EHR system failed to support the fluid volunteer-based human infrastructure of the free clinic.