The dissertation explores criteria for evaluating the performance of trigger mechanisms for determining extended benefit payment periods. A review of the current law is made as well as a brief summary of legislation leading to its passage. A quantitative model using concepts from the Theory of Markov Chains is established which meets established criteria. This model is then fully developed and discussed with respect to variations in the economy and their impact on the model. The model itself may be used as a trigger or may be used as a guide by which to evaluate other trigger mechanisms. A general approach in the implementation of the various models considered emphasizes conceptual matters, due to a lack of readily available data for the empirical study which is appended to the document. (Author/AJ)