Some laboratories or laboratory sections have unique needs that traditional anatomic and clinical pathology systems may not address. A specialized laboratory information system (LIS), which is designed to perform a limited number of functions, may perform well in areas where a traditional LIS falls short. Opportunities for specialized LISs continue to evolve with the introduction of new testing methodologies. These systems may take many forms, including stand-alone architecture, a module integrated with an existing LIS, a separate vendor-supplied module, and customized software. This article addresses the concepts underlying specialized LISs, their characteristics, and in what settings they are found.