Abstract. An international group of scientists is building a ‘trait base’, an open internet database of life-history traits of the Northwest European flora (LEDA) that can be used as a tool in planning, in nature conservation and restoration, and in other applied research. The species-trait matrix will comprise referenced information under control of an editorial board, for species of the Northwest European flora, combining existing information and additional measurements. The focus will be on 26 plant traits that describe three key features of plant dynamics: persistence, regeneration, and dispersability. Currently 35% of the species-trait matrix has been filled; however, as the LEDA trait base consortium aims to deliver a database as complete as possible, all input from the scientific community is welcome.