A review of past and current activities at CEN/TC/38, within the scope of "wood durability, in relation with exposure" suggest that former activities linked to wood preservative efficacy shall formally include the balance safety/efficacy as a main part of the risk/benefit patterns. One way is an extensive development of liaisons. The case of OECD/CEN cooperation on emission assessment is a positive example. Matters of international harmonization ISO/CEN are perceived as maintenance. Risk reduction shows serious potentialities at the local, application stage, which is typically a sector of services aiming to limit the widespread use of substances and doses (baiting, on-site preventive and curative, maintenance), opening a scope of guidance for services where the skill is based on local adaptation, optimization and pre-estimated options. More accurate parameters are necessary to facilitate prescription.