The bainitic transformation mechanism is one of the controversial issues in solid phase transformations on which sharp arguments have lasted for a long time. A lot of research work on this mechanism has been done by both the shear and diffusion schools. Results from these two schools have many differences and the viewpoints on them are different essentially as well The bainitic transformation mechanism is one of the controversial issues in solid phase transformations on which sharp arguments have lasted for a long time. A lot of research work on this mechanism has been done by both the shear and diffusion schools. Results from these two schools have many differences and the viewpoints on them are different essentially as well