  In this paper we present a study of chemical abundances in six star-forming
regions. Stellar parameters and metallicities are derived using
high-resolution, high S/N spectra of weak-line T-Tauri stars in each region.
The results show that nearby star-forming regions have a very small abundance
dispersion (only 0.033dex in [Fe/H]). The average metallicity found is slightly
below that of the Sun, although compatible with solar once the errors are taken
into account. The derived abundances for Si and Ni show that the observed stars
have the abundances typical of Galactic thin disk stars of the same
metallicity. The impact of these observations is briefly discussed in the
context of the Galactic chemical evolution, local inter-stellar medium
abundances, and in the origin of metal-rich stars in the solar neighbourhood
(namely, stars more likely to harbour planets). The implication for future
planet-search programmes around very young, nearby stars is also discussed.
