Covalent inhibitors continue to be developed as treatments for a wide variety of human health conditions, with >35 approved in the last 20 years by the US FDA for use in humans. Many protein targets, especially enzymes, have been found to be effectively targeted by covalent inhibitors for the treatment of human diseases. In this section we focus on some of popular targets for covalent inhibitors, such as the SARS-CoV-2 main protease, RAS proteins, BTK, EGFR and HER2, FGFR, JAK3, and CDK proteins.; We also briefly discuss the use of covalent inhibitors for protein-protein interactions. Structures of compounds discussed in the following section can be found in Supplementary Table .