The vascular network consisting of phloem and xylem (wood) provides plants with structural support and long-distance transport that specifies further downstream processes in the sink tissues (such as wood in a tree trunk or edible storage organ typical for vegetables and fruit). Our group has been pioneering the understanding of phloem development and vascular meristem, (pro)cambial, function in plants. Using the information derived from analysis of Arabidopsis phloem development, we focus on understanding and engineering cambial development in tree species.