Routing algorithms are required to guarantee the various quality-of-service (QoS) characteristics requested by the wide range of applications supported by Broadband Integrated Services Digital Networks (B-ISDNs). In this paper the routing problem is formulated as a fuzzy multiobjective optimization model. The fuzzy approach allows for the inclusion and evaluation of several criteria simultaneously. The proposed model takes into consideration the balancing of the load in the network to avoid link saturation and hence the possibility of congestion. The efficiency and applicability of the model are tested under different load conditions by studying several measures of performance. ᭧ 1998 Published by Elsevier Science B.V. All rights reserved.