The floral ontogeny of the Cyperaceae has only sporadically been studied. However, at the university of Gent this family has been studied intensively for many years whereas our laboratory has a large experience with floral ontogenetic work. SEM and LM techni- ques will be used in order to contribute to a better knowledge of the floral development of the Cyperaceae, in co-operation with the Biology Dept. at the U.G. Next we will also pay attention to the floral ontogeny of the Rubiaceae. The purpose of our research is to examine a wide spectrum of genera of the Rubiaceae. This family has been a long time subject of intensive research at our laboratory, in co-operation with the National Botanic Garden at Meise. Special attention will be paid to the discovery of general patterns in floral development.