Abstract In the design of turbines, the strength of the blades is a matter of great importance since blading is the heart of the turbine. The authors discuss the factors which affect the strength of turbine blades and show what recent progress has been made and what studies are under way toward improved blade designs. The discussion is limited to the full-admission type of blade row which is subjected to steam flow through its full annulus, the most common type of blade row. A discussion of the problems of designing partial-admission rows was given by R. P. Kroon in a paper presented before the Society in 1939.