The caspases are a family of proteases that are essential for the initiation and execution of apoptotic cell death. These aspartate-specific proteases cleave the substrates that ultimately lead to the death of the cell. Members of this family play key roles in regulating additional diverse cellular events, including inflammation, cell division, and other forms of cell death. By engaging these diverse mechanisms, caspases protect against a range of diseases, including cancer, cardiovascular disease, and inflammatory conditions. In addition, engineered inducible caspases have been used in the clinic as a safety switch for adoptive T cell therapy to prevent graft vs host disease. Therefore, the availability of techniques to accurately and specifically measure caspases is essential for us to understand the mechanisms and functions of these important proteases. This collection of methods will describe both standard and new techniques that can be used to measure caspase activation and function. These include in vitro assays to measure caspase activation, model systems, imaging techniques to visualize caspase activation and activity in live cells and whole tissues, and genetic approaches to disrupt caspase activation.