Reversible protein acetylation provides a central mechanism for controlling gene expression and cellular signaling events. Two pharmacological inhibitors of protein deacetylation are currently approved for the treatment of human cancer, and numerous follow-on compounds are in clinical development for oncology and non-oncology indications. The inhibitors target members of a family of enzymes known as histone deacetylases (HDACs). Surprisingly, HDAC inhibitors have also been shown to be efficacious in preclinical models of heart failure. This review highlights roles of HDACs in the heart and the therapeutic potential of HDAC inhibitors for the treatment of heart failure.