This paper aims to enlighten the debate around the increase of instability in contemporary labour markets. Based on the case of France and the UK, we analyse the position in the national employment system of employees, from 30 to 55 years old, concerning their job stability. National employment systems are broken down into four stability regimes created from the stability variable we generate. This variable is calculated on the basis of the ratio of tenure in current job to total time spent in the labour market. Both descriptive statistics of the stability variable and probabilities for employees to joint one regime or another, show the absence of a generalised employment instability for this “central” work force.