This paper provides a simple model to discuss the financing of network expa
nsion (for telecommunications, electricity, water, etc.) in developing coun
tries. It shows how inefficient or corrupt tax systems affect the developme
nt of networks, and restore partially the relevance of cross-subsidies betw
een rich and poor consumers for financing this development. (C) 2000 Elsevi
er Science B.V. All rights reserved. JEL classification: O2; H2; L5.