Top: age-metallicity plot for the Milky Way disk. The contours indicate the relative sample completeness, i.e. the percentage of stars that would remain in the sample due to the Gaia-ESO survey selection functions, i.e. IR magnitude and colour cuts, and restrictions imposed on stellar parameters. Here the magnitude cuts refer to the distance of 1 kpc. For clarity, this fraction was normalised to its peak value. Bottom: the distribution of stars in the [Mg/Fe] – age plane.