In this paper, an approach for modelling and analysing e-Marketplaces based on agents is proposed. The approach is founded on a Statecharts-based specification language and on a Java-based, discrete event simulation framework. The former allows for the modelling of the behaviour of the main agents (stationary and mobile) of an e-Marketplace along with their interaction protocols. The latter supports the execution through simulation of agent-based eMarketplace models. The approach is exemplified by defining and simulating a consumer-driven eMarketplace model which offers mobile agentbased services for searching and buying goods. The simulation phase enabled validation of the emarketplace model and evaluation of the performances of different kinds of mobile consumer agents.