A model of clinical query management is described that supports the integration of various types of biomedical information and the delivery of that information through a common interface. The model extends the architecture of the World Wide Web to include a Common Gateway Interface (CGI) mediator, which takes in user queries, performs syntactic and semantic processing to transform the input to a canonical form, selects the appropriate information sources to answer the query, translates the canonical query statement into a query of each information resource, queries the chosen information sources in parallel, and controls the analysis and display of results. We describe WebMedline, a CGI mediator that implements portions of this model, and discuss the benefits and limitations of this approach.