Expert laboratorians detail emerging methodologies for studying the cell cycle, its kinases, and kinase inhibitors. The authors focus the issues of gene expression in vivo and in vitro, the analysis of cyclin-dependent kinase inhibitors, protein degradation mediated by the proteosome, the analysis of the transformed cell phenotype, and innovative techniques to detect apoptosis. Many of the protocols are new, such as electron microsocopy to detect apoptosis and proteosome-mediated degradation, whereas others study the interactions between protein-protein, protein-DNA, and protein-RNA.