Chrysotile comprises over 95% of the asbestos used today. Some have contended that the majority of asbestos-related diseases have resulted from exposures to the amphiboles. In fact, chrysotile is being touted as the form of asbestos which can be used safely. Causation is a controversial issue for the epidemiologist. How much proof is needed before causation can be established? This paper examines one proposed model for establishing causation as presented by Sir Austin Bradford Hill in 1965. Many policymakers have relied upon this model in forming public health policy as well as deciding litigation issues. Chrysotile asbestos meets Hill's nine proposed criteria, establishing chrysotile asbestos as a cause of mesothelioma.