Building sets of reference stars for current and future spectroscopic survey stellar parameters

One of the main deliveries of spectroscopic surveys are the stellar parameters and abundances that are determined from automatic pipelines. In this talk I will present 2 important sets of stars that have been used to validate and calibrate the astrophysical parameters of not only several spectroscopic surveys but also Gaia DR2 parameters from the BP/RP spectra. These are the Gaia benchmark stars and a sample of solar twins, both developed by our group at the Astronomy Nucleus in Chile. I will discuss our current activities and future plans for the next generation of spectroscopic surveys and further data releases of Gaia