Paramagnetic Ni and Pd complexes have been proposed to play an important role in several organometallic reactions, as well as small molecule activation processes. In this context, a series of uncommon organometallic Ni(III) and Pd(III) complexes relevant to cross-coupling reactions have been isolated and their catalytic reactivity was studied in detail. More recently, unique mononuclear Ni(I) and Pd(I) complexes have been developed and their reactivity was probed for the first time. Finally, the intermediacy of such paramagnetic Ni and Pd species in various organometallic reactions will be discussed.