Carbon nanotube (CNT) functionalisations constitute the major activity within the interdisciplinary fields of CNT nanotechnology. Truly innovative uses of CNTs are presaged to come from the synergetic combination of some of their outstanding properties – chemical robustness, outstanding electrical, geometrical, mechanical, photonic, and electrochemical properties – with additional features that are introduced by chemical functionalisation. In this chapter, we overview recent advances in the rapidly developing area of covalent functionalisation of CNT to integrate them into multifunctional nanoconjugates.