1-Chloro-acetyl-2,6-bis-(2-chloro-phen-yl)-3,5-dimethyl-piperidin-4-one oxime.

In the title compound, C(21)H(21)Cl(3)N(2)O(2), the piperidine ring adopts a distorted boat conformation. One of the chloro-phenyl rings is almost perpendicular to the best plane through piperidine ring, making a dihedral angle of 88.7 (1)°, whereas the other ring is twisted by 71.8 (1)°. The crystal packing is stabilized by inter-molecular C-H⋯O, C-H⋯Cl and O-H⋯O inter-actions.