There are provided NMR contrast agents comprising water-soluble paramagnetic metal chelates, preferably of Cr(III), Fe(III) or Gd (III), wherein the chelating entity is an anilide group containing organic moiety, preferably a compound of formula I
wherein R1 to R5 may represent hydrogen or halogen atoms, optionally halogenated alkyl or alkyoxy groups or carboxyl groups. The agents are especially suitable for use in NMR imaging of the hepatobiliary system.