Stefka has been teaching Biology and Chemistry in English and Spanish since 1991. And since 1998 she has been involved in course development, pre-service and in-service teacher training in the field of CLIL/LSP and subjects taught through a FL. She also works in the field of innovative approaches in language learning/teaching and opportunities for collaboration and cooperation at all levels of educational system. She is a coordinator and/or team member of several projects on CLIL/LSP and has been delivering workshops, seminars and summer schools showing possibilities for collaboration between Subject and Language teachers in order to facilitate Teachers and Students with the language as well as to develop communicative skills. She is a school book author and has many publications in the field of LSP.