What are the driving forces behind the unequal distribution of training after graduation among higher education graduates? Participation in lifelong learning is restricted here to work-related training. The paper aims at examining the mechanisms that cause variation in training rates, by taking into account fields of study, personal competency profiles, preferences, motivation and effort, as well as job and workplace-related characteristics and social- and human-capital related variables. International survey data (the Reflex study) five years after graduation are employed. The results indicate that participation in work-related training is mainly triggered by push-factors at the workplace, as well as by motivational factors. The training rates vary across countries, with an especially low participation rate in Norway, and a high participation rate in Finland. The paper discusses the possible reasons for this variation. (Contains 4 tables, 3 figures, and 6 notes.)