Measles virus (MV) is a negative-strand RNA virus (paramyxovirus) with oncolytic properties. The significant preclinical activity of MV vaccine strains against a variety of tumor models, their potent bystander effect, their selectivity against tumor cells, and their ability to retain their oncolytic properties when engineered and retargeted makes them a promising oncolytic platform. In this article, we review potential applications and challenges associated with use of MV strains as cancer therapeutics.