A methodology for selecting remediation technologies is presented as part of a decision support system for the rehabilitation of contaminated sites. It includes 2 steps: In the 1st step, a pool of suitable technologies is selected within a technologies database according to their applicability to site-specific conditions; in the 2nd step, the selected technologies: are ranked according to a multicriteria decision analysis (MCDA) approach. The MCDA was applied to allow for a transparent procedure and for the integration of expert analyses. The methodology was implemented in a previously developed georeferenced information system-based decision support system for the rehabilitation of contaminated sites and then applied to a case study (Porto Marghera, Venice, Italy). On the basis of the obtained results, the proposed methodology appeared suitable to select remediation technologies according to both technical features and requirements of available technologies, as well as site-specific environmental conditions of the site of concern, such as chemical contamination levels and remediation objectives.