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This paper presents an experimental study of crack shape evolution inmild steel specimens under cyclic loading. It is widely known that the introduction ofcompressive residual stresses by cold working the surface can be highly beneficial inimproving the fatigue performance of structural components. Although it is recognisedthat relaxation of surface compressive residual stress can reduce the potential benefits,the effects of residual stress on crack shape evolution are often overlooked. Previousstudies have shown that the intensity of the surface compressive residual stress has apronounced effect on fatigue crack initiation. A recently developed technique termedcontrolled stitch rolling, which applies differing intensities of compressive residualstress at specific regions in a structure, is shown in the paper to influence fatigue crackpropagation life considerably.