High-quality echelle spectra of a homogeneous sample of 100 QSOs with redshifts between 3.5 and 4.5, covering the spectral range from 315 to 2500 nm, have been obtained in the course of the ESO observing program 'Quasars and their absorption lines: a legacy survey of the high-redshift universe with VLT/XSHOOTER', lead by PI Sebastien Lopez (program code 189.A-0424). This data set represents the largest spectroscopic survey of high-redshift QSOs with simultaneous rest-frame UV/optical coverage to date, thus enabling a wide range of research topics including the intergalactic medium, active galactic nuclei and cosmological studies.

The data, which were reduced and calibrated by the survey team and subsequently returned to the ESO science archive, are now publicly available via the Phase 3 query form. The spectra are corrected for telluric absorption and the QSO continuum fit is provided. For each target there is one spectrum per arm (UV, VIS and NIR) plus the joint spectrum. This release also includes a redshift catalogue and a comprehensive release description.