The purpose of this demonstration is to present the main features of the BioNavigation system. Scientific data collection needed in various stages of scientific discovery is typically performed manually. For each scientific object of interest (e.g., a gene, a sequence), scientists query a succession of Web resources following links between retrieved entries. Each of the steps provides part of the intended characterization of the scientific object. This process is sometimes partially supported by hard-coded scripts or complex queries that will be evaluated by a mediation-based data integration system or against a data warehouse. These approaches fail in guiding the scientists during the collection process. In contrast, the BioNavigation approach presented in the paper provides the scientists with information on the available alternative resources, their provenance, and the costs of data collection. The BioNavigation system enhances a mediation-based integration system and provides scientists with support for the following: ⦁ To ask queries at a high conceptual level; ⦁ To visualize the multiple alternative resources that may be exploited to execute their data collection queries; ⦁ To choose the final execution path to evaluate their queries.