= Integrated into several varieties of MUA =

It's possible to use SpamAssassin with every MUA (Mail User Agent) which supports some kind of "pipe through" filter.

= Integrated in KMail =

For current versions of KMail there's a description on the [[http://kmail.kde.org/tools.html#antispam|KMail Tools]] page. The next version of KMail shipped with KDE-PIM 3.3 will have an antispam-wizard which makes building the filter rules a thing of three clicks.