Wrought magnesium alloys exhibit poor cold formability and the accepted explanation is the shortage of independent slip systems. In order to improve the formability in these alloys, an understanding of the deformation modes is required. In the present work, activation of different slip and twinning systems are investigated in rolled Mg–3Al–1Zn using electron back scattering diffraction. Analysis was performed on deformed surfaces and on metallographically prepared cross-sections following deformation at room temperature. The results reinforce the importance of prismatic slip and c-axis compression double twinning.