This 5-year cooperative agreement will award funds to improve the effectiveness, capabilities, and sustainability of public health laboratories (PHLs)–individually and as components of a national PHL system–in the United States and in other countries that CDC supports. The FOA aims to improve PHL infrastructure, develop a well-trained and maintained PHL workforce, and strengthen the PHL system in order to promote quality and safe laboratory practice in the entire health system as it pertains to public health in the United States and globally. Activities conducted through this cooperative agreement will use science-based knowledge to identify best practices that will improve PHL effectiveness, capabilities, and sustainability.