A second-order discrete transfer function, with a pair of complex poles and one real zero, is assumed to be a model which characterizes the dynamic behaviour of a higher-order discrete system (perhaps, an existing system), or some idealized response. From expressions given in the paper is generated a table of numerical data which provides the means for determining the model's numerator and denominator coefficients from simple performance specifications given in either the time-, frequency- or complex z-domains, and vice-versa, and for converting specifications from one domain to another.