Radiofrequency ablation is increasingly being established as a curative treatment option for atrial fibrillation refractory to antiarrhythmic drug therapy. Especially catheter ablation of atrial fibrillation is associated with significant procedure-related risks, as this is one of the most complex interventional electrophysiologic procedures. Knowledge about common and infrequent complications, incidence, etiology, and techniques for prevention should minimize risk and help to further increase procedural success. This paper intends to provide a practice-oriented summary of international surveys and consensus documents in comparison with data from our own electrophysiologic laboratory. Great attention will be laid upon early recognition and technical as well as procedure-related possibilities to prevent any complication.