(E)-3-[(3-Eth-oxy-2-hy-droxy-benzyl-idene)amino]-benzoic acid.

In the title compound, C(16)H(15)NO(4), a potential bidentate N,O-donor Schiff base ligand, the benzene rings are inclined to one another by 4.24 (12)°. The mol-ecule has an E conformation about the C=N bond. An intra-molecular O-H⋯N hydrogen bond makes an S(6) ring motif. In the crystal, pairs of O-H⋯O hydrogen bonds link the mol-ecules, forming inversion dimers with R(2) (2)(8) ring motifs. These dimers are further connected by C-H⋯O inter-actions, forming a sheet in (104). There is also a C-H⋯π inter-action present involving neighbouring mol-ecules.