The influence of various factors on the thermal shock resistance of plasma-sprayed yttria-stabilized zirconia (YSZ) coatings was investigated. The coatings, formed using different spraying conditions, were repeatedly exposed to a thermal cycle involving a 30 minute heating period at 1200°C followed by a water quench during this study. The results suggest that, for any given YSZ powder, there exists an optimum plasma arc current for obtaining coatings that best endure such severe temperature cycling conditions. Other coating variables, such as spray distance and powder feed rate, are also observed to effect coating durability. Furthermore, the YSZ overlayer thickness and the bond coat material employed are found to be important coating life determining factors. © 1993.