Design and development of sustainable, environmentally benign catalytic reactions for organic synthesis and for energy related processes are major goals of current catalysis. We have developed new efficient, environmentally benign reactions catalyzed by pincer-type transition metal complexes, including complexes of base metals. Several of these reactions either produce hydrogen gas or consume it. Metal-complex catalyzed reactions, in which most of the catalytic activity is ligand-based, were also developed.  Various synthetic and energy-relaed applications based on these catalytic reactions, such as oxidation of organic compounds using water as oxidant liberating H₂, and new liquid organic hydrogen carriers (LOHCs), will be described.