Twenty-four patients undergoing extracorporeal piezohthotripsy took part in this study and underwent treatment on a Wolf Piezohth 2300 Lithotripter, which does not require any type of anaesthesia and enables the patient to be treated as an out-patient Previous work has investigated anxiety states of patients during investigative procedures and found that information given prior to the procedure is beneficial in reducing the levels of anxiety reported Modern urological surgery carried out to remove kidney stones has progressed to non-invasive techniques with the introduction of extracorporeal piezolithotripsy (EPL) However, little work has examined the patient's reaction to this new procedure Since patients undergoing EPL are awake throughout the procedure, it is possible to perform continuous assessment of anxiety by measurement of palmar sweat The results demonstrated significantly increased levels of palmar sweat throughout treatment, with a return to pre-treatment levels afterwards This was demonstrated by just under 50% (n = 10) of patients who appeared to be agitated during treatment, and by the comments made by patients about their treatment One-third of patients (n =8) described pain as far more severe than had been anticipated when asked if they could identify a cause for anxiety. It is recommended that adequate patient preparation and education prior to the procedure should be provided, but that such education must also include a warning that some discomfort may occur