Gas-phase ion spectroscopy has a rich history in giving detailed structural insights into molecular species related to diverse areas of science (e.g. astrochemistry, catalysis, solvation). More recently, there has been an interest in using these cutting-edge techniques to enhance the analytical capabilities of mass spectrometry, and in particular the identification of biomolecules. This development is largely driven by the enhanced structural information that spectroscopy offers compared to the more conventional, lower-resolution approaches of mass spectrometry (e.g. fragmentation, ion mobility). Using the example of infrared ion spectroscopy for the identification of metabolites, the potential for these approaches will be discussed, as well as the many challenges that remain to be overcome, in terms of instrumentation, methodology, and interpretation.