In this article, seven key presenters from the AFMLTA 21st International Languages Conference held on the Gold Coast of Australia in 2017 each contribute three key ideas or challenges for 21st century teaching and learning of languages. Drawing on their eclectic international experience. the contributors canvas ideas from specific pedagogies and approaches to teaching and learning languages; to identifying the need for research and targeted strategies to influence policy decisions, in Australia and internationally; to teacher preparation and curriculum demands to meet the needs of diverse learners. Collectively, the 21 key ideas provide a timely snapshot almost two decades into the 21st century of themes that emerged in the conference, and which percolate through international conversations about the teaching and learning of languages, as evidenced in the research literature. increasing knowledge about the brain and its capacity to learn languages, and the social and cultural contexts in which choices about languages learning occur. The ideas provide important messages for teachers, learners, and administrators of languages teaching programs both in Australia and internationally, as we look ahead into the next few decades.