Techniques for implementing a load balanced server system are described which may be used for effecting electronic commerce over a data network. The system comprises a load balancing system and a plurality of servers in communication with the load balancing system. Each of the plurality of servers may include a respective data cache for storing state information relating to client session transactions conducted between the server and a particular client. The load balancing system can be configured to select, using a load balancing protocol, an available first server from the plurality of servers to process an initial packet received from a source device such as, for example, a client machine of a customer. The load balancing system can also configured to route subsequent packets received from the source device to the first server. Before generating its response, the first server may verify that the state information relating to a specific client session stored in the data cache is up-to-date. If the first server determines that the state information stored in the data cache is not up-to-date, then the first server may be configured to retrieve the desired up-to-date state information from a database which is configured to store all state information relating to client sessions which have been initiated with the server system.