We report from the second ESF Programme on Functional Genomics workshop on Data Integration, which covered topics including the status of biological pathways databases in existing consortia; pathways as part of bioinformatics infrastructures; design, creation and formalization of biological pathways databases; generating and supporting pathway data and interoperability of databases with other external databases and standards. Key issues emerging from the discussions were the need for continued funding to cover maintenance and curation of databases, the importance of quality control of the data in these resources, and efforts to facilitate the exchange of data and to ensure the interoperability of databases.