Australian Standard AS 1288-2006 nominates values of Ultimate Limit State (ULS) design strength for glass which varies with glass thickness & are significantly higher than the value adopted in other Standards. This paper demonstrates that these values are grossly incorrect, & that they arise from fundamental errors of analysis. It is noteworthy that the erroneous ULS design stresses nominated in the AS published in 2006 not only affect the design of glass windows subject to wind load, but also the safety & fitness for purpose of glass designed for all other static & dynamic load conditions including floors & other trafficable areas, balustrades, aquarium, swimming pools and all glass structural elements. A rationally deduced value of ULS design stress based on sound engineering principles, which aligns with other international standards is derived & proposed.