Laparoscopic ultrasound exploration has significantly augmented the range of minimally invasive surgery. In particular it is essential for 3D exploration of the abdomen for staging. Beyond its diagnostic, purposes laparoscopic ultrasound is gaining importance for intraoperative therapeutic support, e. g. imaging of the biliary tree during laparoscopic surgery of the bile duct and for navigation during radio-frequency ablative or resective interventions on the liver and other parenchymatous organs. Compared to other imaging procedures, sonography has still the highest potential for further development. The most progress can be expected in navigated ultrasound.