Description
The observed trends of chemical abundance ratios in the Milky Way provide stringent constraints on nucleosynthesis and models of galactic chemical evolution. Many of us are wondering: are high quality spectra sufficient to obtain accurate (or precise) abundances? I will focus on recent developments in the field of theoretical diagnostic spectroscopy. I will highlight two classes of cases: those that demand more sophisticated modelling with effects of 3D radiation transfer, convection, and non-LTE, and those that are nearly invariant to how we model stellar atmospheres. I will also discuss how the new 3D NLTE models change our understanding of Galactic abundance trends and influence their astrophysical interpretation.