To investigate individual trajectories is to get to grips with career trajectories and initial and continuing training pathways. Céreq analyses all these trajectories and pathways and their evolution, in a context in which there tends to be greater permeability between employment and education/training and between initial and continuing education/training. Céreq bases its studies on field observations, interviews and statistical surveys. Among the last named, the Générations surveys (a national programme that tracks the early years of the working lives of young people with all levels of education and training) and the Defis surveys (on continuing training for employees) provide insights into these trajectories in all their complexity and over their entire duration.