ABSTRACT- CLINICAL COORDINATION CORE The Clinical Coordination Core (CCC) provides oversight for efficient and optimal enrollment of patients with early Lyme disease as manifested by erythema migrans (and/or other features of disseminated early Lyme disease) and for an antibody-based prevalence study of patient populations at high risk of exposure to Ixodes scapularis transmitted tickborne infections. The CCC provides the centerpiece for successful completion of the Aims outlined in Projects 1-3. The CCC directs the collection of clinical information and blood and tissue samples, supports the practice infrastructure for subject retention and follow-up and co-ordinates efficient distribution of samples to the Diagnostics Core. We will develop and maintain an integrated system for data management among the three medical institutions at MaineHealth, Tufts University School of Medicine, and MassGeneral Brigham (MGB). The CCC supports, monitors and, if appropriate, modifies operations for our outpatient –based network of front-line providers of care in high incidence areas for Lyme disease. Our enrollment sites include hospital-based practices, independent primary care sites, and urgent care centers over large geographic areas in New England. Our enrollment strategy incorporates an iterative approach to successful practice site engagement that will maximize enrollment of subjects with early Lyme disease through ongoing interaction with the capacity to augment support if needed. Contingencies for practice site expansion are in place if needed. Detailed protocols for subject enrollment, skin biopsies, phlebotomy and specimen handling will be overseen by the CCC teams at MaineHealth, Tufts and MGB. In addition to our outpatient based networks for enrollment of subjects with erythema migrans in Maine and Massachusetts, the CCC oversees hospital-based enrollment within our network of subjects with early disseminated Lyme disease, i.e. Lyme meningitis and/or other acute neurologic presentations and Lyme carditis. The CCC is closely linked to the Diagnostic Core for integration of subject data, sample distribution and storage. We have created an organizational structure of the CCC that facilitates integration of Project and Core leadership while providing for continuous interaction with our outpatient practice leaders.