Z(2) monopoles in D=2+1 SU(2) lattice gauge theory

We calculate the euclidean action of a pair of Z(2) monopoles (instantons), as a function of their spatial separation, in D = 2 + 1 SU(2) lattice gaug e theory. We do so both above and below the deconfining transition at T = T -c. At high T, and at large separation, we find that the monopole "interact ion" grows linearly with distance: the flux between the monopoles forms a f lux tube (exactly like a finite portion of a Z(2) domain wall) so that the monopoles are linearly confined. At short distances the interaction is well described by a Coulomb interaction with, at most, a very small screening m ass, possibly equal to the Debye electric screening mass. At low T the inte raction can be described by a simple screened Coulomb (i.e. Yukawa) interac tion with a screening mass that can be interpreted as the mass of a "consti tuent gluon". None of this is unexpected, but it helps to resolve some appa rent controversies in the recent literature.