This chapter focuses on the analysis of religion in state schools. It scopes the teaching of religion in private establishments, whether they are entirely run by private bodies, with sole financial autonomy, partially subsidized by the State, responds to different premises. The chapter highlights that the teaching of religion in state schools in Spain is denominational as opposed to non-denominational. It argues that the general rule in England and Wales. This controversy, the parents of the 8-year-old girl in question insisted on the voluntary nature of her decision. In addition to the principles of freedom and non-discrimination, a contextual understanding of the model of Spanish Ecclesiastical Law requires a study of the Constitution. As stated by Martínez Torrón there is no doubt that the solution of the 'religious question' in the Spanish Constitution of 1978 was one of the key aspects behind the success of the democratic transition.