Most current methods for measuring cell death are based on plasma membrane disintegration and the consequent release of cytoplasm. The relevant cells are usually loaded with a label (usually 51Cr or 125I), the release of which is measured. I describe here a method, based on the recent evidence that dying cells often degrade their DNA into small fragments, which measures the DNA retained by living cells rather than the cellular components lost by dying cells. The assay is set up essentially like the current cell lysis assays and harvested like a cell proliferation assay. It is faster, more sensitive, easier to set up, less expensive and safer than the current standard 51Cr release assay.