The InCELL Pulse Target Engagement Starter Kit provides reagents and protocols for the design and development of InCELL Pulse assays for the measurement of inhibitor cellular potency against user-defined protein targets of interest. The assay applies DiscoverX’s proprietary enzyme fragment complementation (EFC) technology to measure liganddependent thermal stabilization of target proteins in a cellular context. InCELL Pulse assays employ a simple protocol requiring minimal hands-on time and enable the measurement of quantitative inhibitor EC50 values. InCELL Pulse assays have been successfully developed for a number of enzymes from diverse classes, including protein kinases, methyltransferases, and hydrolases.