This paper provides a Lyapunov formulation of the cyclic-small-gain theorem for general dynamical networks (large-scale systems) composed of continuous-time input-to-state stable (ISS) subsystems. ISS-Lyapunov functions for continuous-time dynamical networks satisfying cyclic-small-gain conditions are constructed from the ISS-Lyapunov functions of the subsystems. (C) 2011 Elsevier Ltd. All rights reserved.