The 3-methoxy-4-hydroxybenzoic acid or vanillic acid (VA) is a naturally occurring molecule important in winemaking. The spectral fingerprints of VA observed in the infrared and Raman spectra are assigned to fundamental vibrational wavenumbers supported by quantum chemical computations. The surface-enhanced Raman scattering (SERS) of the VA has been obtained in silver colloidal solutions making possible analytical applications for detection of VA at picomole concentrations. Copyright (c) 2008 John Wiley & Sons, Ltd.