Resistometry (in-situ measurement) has been applied during the electrosynthesis of polypyrrole/paratoluene sulfonate and also subsequent to polymer growth. Simultaneous monitoring during polymer growth was also conducted by use of the Electro-chemical Quartz Crystal Microbalance. The resistance changes during cyclic voltammetry of the PPy/PTS characterise the effects of polymer thickness and cationic species of the supporting electrolyte.