Cyclin-dependent kinases (CDKs) are key regulators of the cell cycle. CDKs are active only when bound to their regulator proteins, cyclins. CDK activity is tightly controlled for successful cell division. Since abnormal cell division represents cancer pathology, controlling CDK activity has been shown as a promising therapeutic strategy. In particular, CDK1 plays an important role in mitotic progression. The CDK1 Assay Kit is designed to measure CDK1/CyclinB1 activity for screening and profiling applications, using Kinase-Glo® MAX as a detection reagent.