Hi, Expert itself consumes rule definitions (DRL etc) and data (facts) with which to reason. The DRL can come from a variety of sources, one of which you mention is Guvnor. In this instance a KnowledgeAgent can be used to poll (HTTP) the web-server on which Guvnor resides for the DRL packages. Guvnor itself uses JCR (Apache JackRabbit or JBoss ModeShape, as from 5.2) to storage requirements. JackRabbit can be configured to write to a database. It would be best for you to read about this technology on their websites. Guvnor exposes a REST API (from 5.2) for manipulating various artefacts (DRL etc) however it remains a repository for information. If you were looking for a rules runtime, Drools Server (and I believe Drools Grid) offer some of what you may desire, but I do not know sufficient about them to comment on your integration and interaction. With kind regards, Mike 2011/5/17 Yoann Charpiot <yoann.charpiot(a)gmail.com&gt;