The effects of the Dzyaloshinskii-Moriya (DM) interaction on the magne
tic properties of a spin-1/2 anisotropic Heisenberg system are investi
gated by using a two-spin cluster mean-field (MFA) procedure. We find
for the easy direction model (i.e., D = D z; where D is the DM vector
coupling) a variety of interesting phenomena resulting from a competit
ion between exchange and DM interactions.