In a method for drilling, completing and fracturing a subterranean formation, an electrical potential is applied to oil or synthetic based drilling fluid to increase the viscosity of the fluid and enable the fluid to entrain drill cuttings and proppant. The same base fluid may be used for drilling, completion and fracturing by adjusting the electrical potential and consequently the viscosity of the fluid for the particular application. In fracturing, little or no potential is applied until the fluid enters the zone of the formation to be fractured. High potential is then applied at the fracture point of the formation to effect fracturing and to enable the fluid to transport proppant into the fracture.