In recent decades, mAbs have emerged as therapeutics. Nine mAbs have been approved for cancer therapy. However, the efficiency of mAbs is far from optimal, and antibody engineering is actively used to improve the molecules. Because of their ability to simultaneously bind two different antigens, bispecific antibodies are unique, and their wide potential as targeting reagents has been demonstrated over the years. However their use as therapeutics has been restrained by manufacturing challenges. Several new recombinant formats have changed the situation. Innovative molecules have led to impressive preclinical and clinical results, and hold great promise. This review presents an overview of the most promising candidates.