e-REC (e-Reporting Of Rare Conditions) is an electronic reporting system designed to understand the occurrence of rare endocrine and bone conditions. Reporters submit monthly reports on new encounters of a small group of conditions that they have agreed to notify and unique IDs are automatically generated for each reported case. Currently, conditions that are included in the e-REC are those that have been specified by the European Reference Networks, Endo-ERN and ERN-BOND listed in the Conditions Dictionary below. The e-REC platform can also be used for surveillance projects such as the ESE RD COVID19 initiative. Please contact the EuRRECa team if you are interested in developing an e-reporting programme for a condition that is not covered at the moment.