Hello! Sorry i've forgot to put a subject in my last mail. It will not happen again! I'm a newcomer to the Zope's world. For now i'm just checking out some features and trying to build some programs on my own. After this blablabla here is main main concern for now: How can i define session properties or objects? What i whant to do is to be able to define any object (say, client id in a web store) as a session variable. The tricky thing is that i do not whant the content of this object to go back and forth between the browser and the server. I do have to put it in the server and access its contents in some session context. The client id in my case is very important and represents a security flaw if i allow to be altered during a browser session. This object is must be defined when the client logs in the application. If i did allowed it, any user could for example update or access some record in a SQL database that did not concerned him. Just because this client id is indeed the identification number of the user in my database model.