A key prerequisite to ensure that payment for ecosystem services is effective is that the management measures landowners are paid to undertake are in fact additional to the status quo and hence bring about a change in provision.

We investigated Danish forest owners' preferences for conditional contracts for the provision of ecosystem services in Natura 2000 policies in a sample covering 12.5% of the total private forest area. This involves allowing old trees to decay naturally, setting aside forest areas, accepting a fixed percentage of broadleaves and increasing access for the public. Forest owners may already provide some of these, e.g., if they derive private benefits from them, in which case additionality becomes an issue. This study investigates the link between forest owners' current management and their willingness to accept (WTA) payments for providing specific ecosystem services by eliciting current practice prior to a choice experiment on contracts. For most of these ecosystem services, owners differentiate their WTA significantly according to their current management. Owners who did not provide extended access had a mean WTA of €14/ha/year for accepting access up to 15 m from roads and paths and €28/ha/year for accepting access everywhere in their forest. However, forest owners who already allow extended access have a mean WTA around zero.