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The effect of cold rolling on crack shape evolution was investigated byexperimentation. A recently developed technique termed stitch rolling, which appliesdiffering intensities of surface compressive residual stress at specific regions in anengineering structure, was adopted to introduce compressive residual stress onto testspecimens to control both the rate and shape of crack propagation. Three BS 7191Grade 275A mild steel plates having undergone different cold rolling procedures weresubjected to medium cycle fatigue tests under bending. Fatigue crack growth wasperiodically monitored using crack sizing non-destructive testing methods and resultsare presented in terms of crack shape evolution. The different cold rolling procedureswere seen to have a significant influence on the crack initiation, crack propagation pathand the overall fatigue life of the specimens. The fatigue lives of stitch rolled specimenswere significantly improved. In addition, cold rolling was observed to have causedcrack arrest and retardation. Comparisons with an analytical fracture mechanicssolution is also presented.