This thesis explores the use of bioimpedance measurements within the field of electrosurgery. A standard monopolar electrosurgery setup has been utilized in order to discriminate between the characteristic impedance of the proper hepatic artery (PHA) and common bile duct (CBD) in domestic pigs. The end goal is to aid a surgeon performing a cholecystectomy, primarily laparoscopic, in order to avoid dividing or damaging the wrong part of the arteries or ducts in the area surrounding Calot s triangle. It could also be a potential building block for further research into for example smart electrosurgery knives or other tissue discrimination for use within electrosurgery. The Valleylab E1551X, E1450G and E1475X electrosurgery electrodes has been evaluated. The E1551X blank stainless steel electrosurgery electrode was chosen as the most optimal electrode to use during the experiments. Basic characteristics of this electrode and its sensitivity field have been measured through a series of experiments using a cucumber model. A total of 9 in vivo pig experiments were performed between March and June 2013 at the Institute for Surgical Research at Oslo University Hospital. Impedance measurement data has been collected from the pig experiments using the Solartron 1260/1294. The measurement locations consists of the common bile duct, proper hepatic artery, gall bladder, right lateral lobe of the liver, hepatic lymph node, splenic artery and spleen. The measurement results for the CBD and PHA has been statistically analyzed. The proper hepatic artery was found to have overall lower impedance than the common bile duct over almost all frequencies. The results show a statistical significant difference between the CBD and PHA in 6 out of 9 pigs (66%) according to the Mann- Whitney U test. Among these, 5 out of 9 pigs (55%) supported the hypothesis that the phase for the PHA was higher than the phase for the CBD at 630 kHz. 1 out of 9 pigs (11%) were a false positive. The result is based upon what part of the phase data had the most amount of statistically reliable results. The hypothesis is tested with an arithmetic mean test for all of the measurements series combined.