The beneficial effect of cardiac resynchronization therapy has been demonstrated in large clinical trials. However, on an individual basis 20% to 30% of patients receiving this therapy will lack improvement or even deteriorate. A better selection of patients to predict response to cardiac resynchronization therapy is therefore needed. Echocardiographic studies have clearly demonstrated that the presence of intra-ventricular dyssynchrony is an important factor determining response to resynchronization therapy, whereas interventricular dyssynchrony appears to be of less importance. Of the different echocardiographic approaches aimed at prediction of response to resynchronization therapy, literature suggests that tissue Doppler imaging may represent the best method. Ongoing research trials will further define the role of other new bi- or three-dimensional echocardiographic tools in the clinical management of patients with heart failure.