The Longitudinal Surveys of Australian Youth (LSAY) program studies the progress of several groups of young Australians as they move from school into post-secondary education and work. This series of documents provides supporting information for the LSAY dataset of the 2003 cohort (Y03) at wave 1 (2003). It includes a questionnaire, frequencies and data dictionary. This report, published by the Australian Council for Educational Research (ACER), is part of the Longitudinal Surveys of Australian Youth (LSAY) research program.