Abstract: A method for enhancing the recovery of oil from underground formations includes alternately using a single bore hole as an electrode well and a producing well by placing a first electrode in electrical contact with the oil-bearing formation through the bore hole and passing electrical current through the oil-bearing formation which has been infused with an aqueous electrolytic liquid to a second larger electrode in electrical contact with earth material, and creating sufficient heat and current density proximate the first electrode to precipitate a local exothermic electrochemical reaction producing hot gases which pressurize the formation, thin the oil and break the oil out of the formation matrix. After the formation has been adequately conditioned by the reaction, oil is produced from the bore hole where the beneficial aspects of the reaction are greatest. Preferably, the electrical current employed is alternating current having a substantially rectangular waveform.