Enzyme Activity in Single Cells, Volume 628, the latest release in the Methods of Enzymology series, discusses groundbreaking cellular physiology research that is taking place in the biological sciences. Chapters in this new release cover Spatial and temporal resolution of caspase waves in single Xenopus eggs during apoptosis, Spatial and temporal organization of metabolic complexes in cells, Measuring cellular efflux and biomolecular delivery: synthetic approaches to imaging and engineering cells, Slide-based, single-cell enzyme assays, Single-cell assays using integrated continuous-flow microfluidics, High-throughput screening of single-cell lysates, Microfluidic capture of single cells for drug resistance assays, and much more.