Ericales sensu APG is a newly defined order of flowering plants based on molecular data. Morphologically as well as wood anatomically, this group is heterogeneous. Hence, the diversity in the secundar xylem in the order asks for a detailed investigation. Therefore, the remaining wood anatomical gaps (paleotropic Sapotaceae, Ericaceae, and Marcgraviaceae) will be filled up with the aid of LM and SEM observations. Next, the phylogeny of the order will be studied on the basis of cladistic analyses. At first, only wood anatomical characters will be used; later on, these data will be extended with other morphological and molecular data. Finally, a cladistic analysis based on this large data set will be carried out. In this way, not only the interfamilial relationships of the order will be studied, but also the evolution of wood anatomical characters.