. A micro-mechanical model of stress-induced martensitic transformation in shape memory alloys is presented. A laminated microstructure of austenite and martensite phases is assumed along with a time-independent thermodynamic criterion for phase transformation. In numerical examples, the pseudoelastic behaviour of single crystals of CuZnAl and CuAlNi shape memory alloys is investigated. Several aspects are examined, including the effects of the loading direction, external constraints, detwinning, and instability of macroscopically uniform transformation.