Evaluating corrosive potential and impressingeffective cathodic current levels based on surface methodologies exclusively are insufficient to effectively protect most wellbore casings. The time-honored solutions ofinhibited drilling muds, isolating primary cement jobs, squeezecementing, and material considerations do not provide a cost-effectivemeans to address downhole corrosion in the Texas Panhandle region. Accurate emplacement of cathodic protection systems is the key. The CPET* Corrosion and Protection Evaluation Tool effectively measures the corrosive profile and corrosive rates in the wellbore environment. This allows the operator to optimize his corrosion prevention expenditures.