By means of a review of the literature and basing on own results the possibilities of sonographically guided ontarget therapeutic interventions are disumed. Puncture of pleura, pericardium and in ascites can be performed with maximum safety. Therapeutic drainage of the effusions succeeds to practically 100 per cent. Punctures of custsare performed only if the lesions are symptomatic; sclerosing of renal cysts has a success rate of 65-80%, that of hepatic cysts up to 96%, ovarial and pancreatic cysts up to 90%. Since, however, the latter recur rapidly, permanent success can be rated as amounting to only 7%. Abscesses are punctured in installments or drained, depending on their size, shape and extension. Here, too, success rates achieved via on-target therapy guided by ultrasound are between 80 and 95%. First results obtained with ultrasound-guided on-target cholecystotomy in cases of colecystitis are encouraging; the disease pattern can be improved in at least 63% to 94% of cases, although the rate of complications is 8-12% and hence relatively high. Other techniques are also discussed, such as gastrostomy, nephrostomy, cholangiography and pancreaticography. Local on-target ultrasound-guided tumour therapy, especially of the primary hepatic cell carcinoma using highly concentrated alcohol results in a definitely longer survival period of the treated patients.