An analysis of the phenomenon of combining work and study amongst university students is made using data obtained from surveys of graduates carried out four years after finishing their degrees. First, the article reviews the evolution of the phenomenon over the last ten years, taking into account the Catalan University Quality Assurance Agency (AQU) labour market insertion surveys for 2005, 2008, 2011 and 2014. Second, the 2008 and 2014 waves are compared to analyse the impact of the economic crisis. In this case, how combining work and study affects academic results and labour market insertion is studied, in addition to whether or not differences occur according to the family's educational background. A random stratified two-stage sampling is used to obtain the results; descriptive and ANOVA analyses with different factors are performed. The evolution shows how the numbers of students who combine work and study has increased, especially among those whose parents have little education. Furthermore, this means that lower marks are obtained and that there is a greater degree of inequality in labour market insertion, depending on the educational background of the family of origin. In general, the relationship between the different variables shows how combining work and study has negative effects on marks but positive effects on labour market insertion, especially if the work experience whilst at university is related to the studies.