The durability of thermal barrier surface coating systems (TBC) remains a crucial issue for turbine engine components, especially at the increased operating temperatures and extended exposure times required for current and new engine designs. TBCs provide critical insulation to maintain lower component temperatures and reduced corrosion, resulting in improved reliability with reduced lifecycle costs. A nondestructive inspection capability has been developed that can quantify the microstructural changes in surface coatings from initial manufacture through end of life. Positron Systems’ Distributed Source Positron Annihilation (DSPA) technology is a portable, surface/near-surface inspection tool that has the capability to quantify microstructural changes in surface coatings and treatments. DSPA has demonstrated the ability to quantify operational damage accumulation in surface coatings, providing early indications of impending spallation and assessment of the relative effectiveness of competing coating systems. The DSPA technology will lead to improved surface coating/treatment procedures, extended TBC lifetimes and optimized TBC formulations.