The N3C Data Enclave is a secure portal containing a very large and extensive set of harmonized COVID-19 clinical electronic health record (EHR) data. The data can be accessed through a secure cloud Enclave hosted by NCATS and cannot be downloaded due to regulatory control. Broad access is available to investigators at institutions that sign a Data Use Agreements and via Data Use Requests by investigators. The N3C is a unique open, reproducible, transparent, collaborative team science initiative to leverage sensitive clinical data to expedite COVID-19 discoveries and improve health outcomes.