This report presents an implementation of the Event Calculus [KS86, Ser90, Sha90b, Sha90a] under the contraint logic programming language CLP (R) Constraint logic programing [JLM86, JL86, JL87] is then put into context; its advantages and limitations are judged and proposal for solutions are made. The description of the implementationis given in phases corresponding to levels of increasing difficulty. All phases are meant to follow a genral scheme so that the examples under consideration should be solved under all phase.