The multidisciplinary and triple-stakeholder approach used to assist step 2 should support also step 3, which selects the bundle(s) of attributes to be valued. The main goal of step 3 is to elect bundle(s) of attributes (different combinations of NCOs at different levels) that can be correctly specified in economic terms and that can be effectively provided at the
spatial and temporal scales. Establishing these bundles as particular landscape functions, as done by Schmitz et al.
(2003), is a possibility. At this level it is important to identify and to model the interrelations between attributes bundled.
Bio-physical data and economic modelling appear to be useful tools to assist this task.