This paper presents the outcomes of a Spanish study on aspects of the background, skills and perceptions of three groups of teachers -- content teachers, language teachers and language assistants -- working to implement CLIL in the monolingual area of Andalusia, Spain. The research was based on a questionnaire completed by 130 informants and highlights teachers' perceptions on training and development needs, participation in courses and exchanges abroad ('mobility') and the coordination and organisation of their programmes. It also examines how variables such as type of teacher (content, language or assistant), level of English and teacher status influence responses. In general, the teachers were positive about their involvement in the CLIL programme, but content teachers were typically less confident in relation to aspects of CLIL implementation than language teachers. There was a general perception that content teachers and language assistants needed greater support to work effectively in CLIL. Somewhat surprisingly, there did not appear to be widespread uptake of mobility opportunities, nor was there any evidence of teachers having opportunities for study leave to develop their CLIL specialism, although there was general satisfaction with local programme coordination. In discussion of our results, we highlight the need for stronger specialist teacher education infrastructure to support CLIL implementation, in particular at university initial teacher education level.