  The boundary effects in the screening of an applied magnetic field in a
finite temperature 2+1 dimensional model of charged fermions minimally coupled
to Maxwell and Chern-Simons fields are investigated. It is found that in a
sample with only one boundary -a half-plane- a total Meissner effect takes
place, while in a sample with two boundaries -an infinite strip- the external
magnetic field partially penetrates the material.
