Chat conversation persistency is one of interesting aspects of chat tools which make them even more useful as a communication medium. However, persistency alone is not useful unless there are features that support persistent conversations in order to increase the usability of a persistent environment. Moreover, these features simplify the processes of conversing and information retrieval for chat participants. This paper uncovers how different persistent chat tools have tried to overcome such difficulties by employing design factors and strategies. Design factors are concerned with the particular functionality of a feature and they are generally concepts that the chat tool should support. Design strategies concentrate more on the rules and restrictions applied to the users and the features available in the tools. A set of design factors and strategies for persistent chat conversation is presented and discussed in relation to the features that support persistent chat conversation.