Technical advances have considerably improved the quality of imaging by transthoracic echocardiography in recent years. This has allowed access to information formerly reserved for transoesophageal investigation. As a result, certain changes in the indications of transoesophageal echocardiography have come about in clinical practice. The best example is probably in the evaluation of mitral regurgitation. The possibilities of accurate description of mitral valve anatomy and of reliable quantification of the lesion have reduced the indications of transoesophageal echocardiography in this pathology. In other indications, such as suspected endocarditis, the investigation of systemic embolism or dissection of the aorta, transoesophageal echocardiography is irreplaceable but the additional information obtained compared with transthoracic echocardiography is less.