Current pharmacological treatments for atrial fibrillation (AF), the most common form of cardiac arrhythmia, have only modest efficacy and are associated with significant risks, including pro-arrhythmia. However, in recent years substantial efforts have been invested in developing agents that target the underlying pathology of AF. Dobrev and colleagues review the molecular mechanisms of AF and discuss promising novel therapeutic approaches, such as the prevention of remodelling processes and the modulation of specific ion channels. The treatment of chronic pain is another area in which there is a major need for novel pharmacotherapies that exhibit greater efficacy, better tolerability and wider safety margins. In their Review, Roques and colleagues discuss the endogenous opioid and cannabinoid systems involved in pain control, comparing the antinociceptive effects of inhibitors of enkephalinases and fatty acid amide hydrolase — the enzymes responsible for opioid and cannabinoid metabolism, respectively. In the third Review, Hogarth and Pietersz review the structure, function and biology of antibody Fc receptors (FcRs), which mediate immune responses upon binding to antibody–antigen complexes. They focus on strategies to manipulate FcR function to treat immune complex-mediated inflammatory disorders as well as approaches to improve antibody-based anticancer therapies. Finally, this month we are featuring a poster and video illustrating advances in anticancer immunotherapy — a field in which recent encouraging clinical trial results for various approaches are heralding a new era. The poster and video were produced with support from Bavarian Nordic and Dendreon, and are freely available at http://www.nature.com/nrd/posters/cancerimmuno. As always, Nature Publishing Group carries sole responsibility for all editorial content.