This chapter discusses the use of mass spectrometry for the authentication of artwork and its transferability to forensics. The general process for art authentication is first discussed. An overview of the main mass spectrometry techniques that are currently used for art authentication is provided, along with commentary on the associated sample preparation and the data that can be obtained. Five examples of real authentication cases, where mass spectrometry techniques were used, are reported with the lessons learnt from them. Finally, the potential for the use of these analytical techniques during criminal prosecutions involving art is discussed, while also highlighting the numerous challenges that one may encounter.