With this identification key, for the first time the determination of each Cupressaceae taxon is possible, as well as the flexible identification of different types of specimens (like female cones, vegetative specimens, herbarium specimens, specimens from cultivars etc.). The identification may be started with any character. The use of the interactive key needs nevertheless some experience. Especially the identification of the large genera Callitris, Cupressus and Juniperus as well as the identification of the subspecies and varieties is partly tricky. The identification of these taxa requires precise measuring as well as a precise assessing of character states, which is often only possible with a strong lens or a dissecting microscope.