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Background: As Motor Neuron Disease (MND) involves a progressive deterioration in nerve function, it is possible that risk factors for the disease will also accelerate the progression of the disease. Methods: This paper uses the two stages of age at onset and age at death to measure progression. Conventional parametric survival models are used to identify significant covariate from a large number of variables which have been suggested as risk factors for “MND / Frailty” models are used to characterize more fully the two stage progression process. Results and Conclusions: The results suggest the polluted work environments are associated with early onset of MND. Although there is a negative dependence between duration from onset to death and age at onset, this is not necessarily inconsistent with the expected progressive deterioration; there is a tantalizing suggestion from the frailty modeling that this may be the net result of a positive association due to variation in the rate of progression over the population and a negative association due to the direct effect of age (for example, because the elderly are more at risk from infections).