Cardiac resynchronisation therapy (CRT) has opened up new perspectives over the past 10 years for highly symptomatic patients with severe systolic heart failure. The present article analyses and comments on recent publications which have lead to an expansion of the indication to patients with mild symptoms of heart failure, and which resulted in the modification of current European guidelines in 2010. The data available from narrow QRS complex studies are critically examined. Furthermore, the latest technical innovations in the field of CRT, which have helped to ease the implantation procedure and achieve higher success rates, are presented. Finally, new wireless ultrasound technology to stimulate the left ventricle, currently in an early clinical phase of evaluation, is presented as a potential alternative in the future.