The NCATS National COVID Cohort Collaborative (N3C) Data Enclave, a centralized and secure data platform featuring powerful analytics capabilities for online discovery, visualization and collaboration for researchers studying COVID-19. The data are robust in scale and scope and are transformed into a harmonized data set to help scientists study COVID 19, including potential risk factors, protective factors and long-term health consequences. The N3C Data Enclave is anticipated to be one of the largest collections of data on COVID-19 patients in the United States. Data analysis within the enclave is supported by both R and Python, the most widely used open-source platforms for statistical analysis and data science. Researchers requesting access to, or working within, the enclave are encouraged to assemble collaborative teams with diverse expertise in such areas as clinical research, statistical analysis and informatics to make the best use of the N3C Data Enclave. A core tenet of the enclave is that it is both accessible and secure, allowing researchers to pursue research in a safe environment conducive to collaborative discovery while also allowing for the deployment of a wide variety of open source tools and components.