Storing a message in a conversation involving a contact of a contact center and an agent of the contact center includes receiving, by a computer of the contact center, the message, wherein the conversation comprises a plurality of messages and then a) identifying redundant information in the received message that is redundant based on one or more of the plurality of messages; and b) identifying derivable information that is derivable from a data source external to the received message. Next, a modified message is generated by eliminating the redundant information and the derivable information from the received message; and the modified message is stored. The modified message can include a number of separate parts, each selectively compressed by a respective compression algorithm.