In 2017, National Center for Supercomputing Applications (NCSA) at the University of Illinois at Urbana-Champaign (UIUC) established a pilot internship program for cyberinfrastructure (CI) professionals. The program, funded by NSF's Office of Advanced Cyberinfrastructure (OAC) (award 1730519), was designed to address the shortage of a workforce with the specialized skills needed to support advanced CI operations. The program was envisioned to provide internship opportunities for individuals who want to gain first-hand experience in the CI operations at a supercomputing center, and develop and refine instructional materials to serve as a template that is openly distributed for use by other centers and institutions to train CI professionals. Program interns are selected from a pool of applicants with the main selection criteria of having a completed classwork equivalent to an associate degree and a demonstrated interest in a career in CI operations. Interns work directly with a group of NCSA engineers in one of the areas of CI focus to gain hands-on experience in the deployment and operation of high-performance computing (HPC) infrastructure at a leading HPC center. The expectation is that interns will enter a workforce that will develop, deploy, manage and support advanced CI at other universities, centers, and industry to meet the needs of the national computational science research community across academia and industry.