In this paper, an Erlang-based stochastic model for patient flow is presented. The model is proposed as an effective tool to obtain analytic results for the stochastic process of patient flow in a health care environment. Through the use of two previously published examples, it is shown that the stochastic model can be developed quickly, is not computationally intensive and provides a good representation of the empirical patient flow. 2000 Elsevier Science Ltd. All rights reserved.