The effective management and timely performance of multi-site, environmental due diligence has always represented a challenge to both consultant and client. However, use of readily available database management tools and the worldwide web can provide a significant advantage in the control and presentation of critical transaction data. As part of a multi-national site transaction, we developed an interactive, web-based technique that allows the integration of commercial databases, site inspection and historical information. Using this approach, we plotted the location of each site with links to Excel-based spreadsheets that included an estimate of potential environmental liabilities (best case/worst case), the basis for each estimate and related supporting information (air photos, Sanborn maps, etc.). Once established, the database offered immediate access, on a secure web site, to the client and the client’s business consultants. In addition, we were able to modify and update database information immediately and without the need for hard-copy (paper) reports.