  We propose a duality for N=2 d=3 Chern-Simons gauge theories with orthogonal
gauge groups and matter in the vector representation. This duality generalizes
level-rank duality for pure Chern-Simons gauge theories with orthogonal gauge
groups and is reminiscent of Seiberg duality in four dimensions. We perform
extensive checks by comparing partition functions of theories related by
dualities. We also determine the conformal dimensions of fields using
Z-extremization.
