An electrosurgical tool or pencil for use in performing surgery includes an elongate, non-conductive housing having an elongate passage extending from a front end. An elongate electrode is mounted in the passage and slidable therein and has an operating forward section, an insulated central section, and an non-insulated rear section. The electrode can be adjusted in its longitudinal direction by a user. A conducting member is mounted on the rear section of the electrode and an elongate conducting strip is fixedly mounted in the elongate passage adjacent one side of the electrode and parallel thereto. The strip is supported by the housing so as to be in electrical contact with the conducting member which is slidable relative to the conducting strip. A circuit board for controlling the tool's operation is mounted in the housing and connected to the conducting strip.