Certificate of need (CON) laws in 21 states restrict acquisition of imaging equipment, including magnetic resonance imaging (MRI), computed tomography (CT) and positron emission tomography (PET) scans. We compare the effect of CON regulations for imaging services provided by hospitals and other providers to determine whether CON laws affect use of imaging services across provider types. We find that services by nonhospital providers, but not by hospital providers, are negatively associated with CON laws. We also find that CON laws reduce the overall number of medical providers, suggesting less availability of imaging services in CON states. Read more.