This chapter will focus on the methods of synthesis of phosphorus-containing dendritic architectures, mainly of phosphorhydrazone type, but also on other types of phosphorus dendrimers. The different types of cores, branches and surface functionalities of phosphorhydrazone dendrimers will be displayed. An overview of the field will be given, concerning not only regular dendrimers, but also dendrimers with layered architectures, dendrons and various types of less symmetrical dendritic architectures, all based on phosphorus derivatives. The properties of these compounds will be briefly highlighted in the final part of this chapter, covering in particular catalysis, nanomaterials, biology and nanomedicine.