Multilingualism does not enhance further language learning in learners if they are not supported by the school environment. Learning L3, L4 or Ln is attained best when language users take advantage and are aware of the existence of their overall linguistic knowledge. It is the teacher whose understanding and beliefs about multilingual pedagogies are central as they affect the manner in which they facilitate a language learner's multilingualism. This study investigates L3 foreign language teachers' beliefs about multilingualism and multilingual pedagogies in two secondary schools in Warsaw, Poland. The first part of the paper gives some background information regarding language learning in Polish schools with an emphasis on a multilingual perspective. In the second one, the collected data were analysed in a qualitative manner to reveal some recurring topics of language awareness, prior linguistic knowledge, cross-linguistic influence, the use of multilingual pedagogies and the auxiliary role of L2 English.