A publish/subscribe messaging network in which a distributed set of publish/subscribe brokers comprises a first subset of publish/subscribe brokers, each arranged to store proxy subscription information for the whole of the distributed set of brokers; and a second subset of publish/subscribe brokers, each configured to send subscription information for local subscribers to one or more brokers within the first subset of publish/subscribe brokers, and configured to request, from a broker within the first subset of brokers, proxy subscription information following receipt of a message.