Aside from official works, the first study on vertical trade unions appeared in 1976, the same year in which the Spanish Trade Union Organisation Organización Sindical Española – OSE was dissolved and its administration became part of the short-lived Institutional Administration of Socioprofessional Services Administración Institucional de Servicios Socioprofesionales – AISS.¹ This study is, of course, Manuel Ludevid’s book. Four years later, a new work appeared entitledVertical Trade Unionism and the Composition of the Francoist State.² Both books, but especially the latter, can be considered pioneers in the study of vertical trade unions. What is more, they have undoubtedly had an