Ammonia borane NH3·BH3 is considered a promising material for hydrogen storage and release, and is attracting increasing attention as a relatively inexpensive, atom economy-convenient and viable reagent for developing new green synthetic transformations. The present review offers a wide overview on the use of AB in the reduction of organic compounds, and highlights the versatility of this reagent, due to the possibility of modulating its activity employing different strategies, which include the use of transition metals, p-block species, organocatalysts and FLP systems.