CuAAC chemistry is used to compose incredible synthetic molecular architectures and acts as a true click chemistry reaction allowing densely functional molecular fragments to be joined in a highly controlled manner. Using supercatalysts based on our mechanistic understanding and in the absence of oxygen, CuAAC reactions are superior even in bioligation chemistry. The catalytic cycle provides an organometallic intermediate reacting through electrophilic or oxidative escape valves resulting in trisubstituted 1,2,3-triazoles and allowing CuAAC-multicomponent reactions. The ease of CuAAC provides new pathways in the development of exquisitely selective macrocyclic protein–protein interaction inhibitors (PPIs) and enzyme inhibitors as putative novel classes of pharmaceuticals.