Vocational education and training is more complex than academic education. It is also subject to important differences among countries due to at least two factors: a) the particular fabric of the productive system of the country and b) the involvement of social actors (employers and unions) as well as the labor market relations and the balance between capital and work. Historical and comparative vocational education and training has deployed a series of analytical tools which have contributed to identify different patterns of existing vocational education systems. Some institutions have also worked in order to help vocational education advance in the past decades: among these, the European Center for the Development of Vocational Training (Cedefop) has twice devised future scenarios in Vocational education, at the turn of the 20th century and right before the COVID-19 pandemics. The combination of current VET systems and suggested scenarios indicate that transformations are subject to negotiation among actors within countries (administration, employers, unions, teachers) and across countries; as well as subject to legitimation of decisions before the wider society. The sociology of conventions is a useful approach to analyse processes of negotiation and legitimation behind historical developments in VET systems; we suggest applying it to tackle current VET scenarios.