Document management systems are needed for many business applications. This type of system would combine the functionality of a database system, (for describing, storing and maintaining documents with complex structure and relationships) with a text retrieval system (for effective retrieval based on full text). The retrieval model for a document management system is complicated by the variety and complexity of the objects that are represented. In this paper, we describe an approach to complex object retrieval using a probabilistic inference net model, and an implementation of this approach using a loose coupling of an object-oriented database system (IRIS) and a text retrieval system based on inference nets (INQUERY). The resulting system is used to store long, structured documents and can retrieve document components (sections, figures, etc.) based on their text contents or the contents of related components. The lessons learnt from the implementation are discussed.