We construct the general O(N)-symmetric non-linear sigma model in 2+1
spacetime dimensions at the Lifshitz point with dynamical critical exponent
z=2. For a particular choice of the free parameters, the model is
asymptotically free with the beta function coinciding to the one for the
conventional sigma model in 1+1 dimensions. In this case, the model admits also
a simple description in terms of adjoint currents.Comment: 23 pages, 2 figure