Complex [Co(PPh3)(2)Br-2] possesses intermediate magnetic anisotropy, D/hc = -13 cm(-1). It displays superparamagnetic behavior either in the absence of the magnetic field or in fields of B-dc = 0.05, 0.1, 0.15, and 0.2 T. At B-dc = 0.1 T, the barrier to spin reversal U/k(B) = 37 K and the extrapolated relaxation time tau(0) = 9.4 x 10(-11) s confirm its classification as a single-molecule magnet. At B-dc = 0.2 T, two relaxation processes are evidenced.