Dual eye-tracking (DUET) is a promising methodology to study and support collaborative work. The method consists of simultaneously recording the gaze of two collaborators working on a common task. The main themes addressed in the workshop are eye-tracking methodology (how to translate gaze measures into descriptions of joint action, how to measure and model gaze alignment between collaborators, how to address task specificity inherent to eye-tracking data) and more generally future applications of dual eye-tracking in CSCW. The DUET workshop will bring together scholars who currently develop the approach as well as a larger audience interested in applications of eye-tracking in collaborative situations. The workshop format will combine paper presentations and discussions. The papers are available online as PDF documents at http://www.dualeyetracking.org/DUET2011/