Biofilms might result in healthcare-associated infections and substantially impact healthcare delivery. Bacteriophage (phage) has been used to treat infectious diseases in humans and there is interest in phage to control biofilms. Phages propagate in their bacterial host and many phages produce depolymerases that hydrolyze biofilm extracellular polymers. Drawbacks of phage to consider include narrow host range, bacterial resistance to phage and phage-encoded virulence genes that can incorporate into the host bacterial genome. The immune system might inactivate phage, and impure phage preparations could contain endotoxin. Phage mixtures or engineered phages could provide effective strategies to overcome these obstacles. Lytic bacteriophages could become a new class of anti-biofilm agents.