Content and language integrated learning (CLIL) has emerged in European education as an effective method to enhance and reinforce students' competence in English and skills while covering traditional content areas. This paper presents a research study into CLIL in secondary education in the area of Castellón in the Valencian Community, Spain. Our first objective of this work involves defining whether some content subjects in some secondary schools of the area are being delivered using English as the vehicular language or not. Secondly, the study also pursues to detect the attitudes and background of the English-language and the content teachers of those centres in relation to CLIL by means of two types of CLIL questionnaires. Results show that even though CLIL has not been introduced officially in any of these secondary schools, some of the teachers have already applied it in specific modules of nursery and primary education. English and content teachers show a positive attitude towards the effects that CLIL could have on their students, and they are eager to cooperate in its implementation.