Specialist arts and music teachers around the world experience intense feelings of professional isolation. Such feelings lead to negative consequences on their professional growth, psychological well-being, and ultimately student learning. It is therefore urgent to identify and implement effective policies to foster collegial support and networked learning among these teaching professionals, as well as collaboration with other stakeholders. After reviewing the literature of teacher isolation, the article presents four sections. The first one focuses on the important role that formal (top-down) school-university partnerships may play in remediating teacher isolation. The "Institutional Program for Pre-Service Teachers Education" (IPPSTE), implemented by the Brazilian Federal Government since 2009, is used to illustrate how arts and music teachers can effectively benefit from collaborating face-to-face with student teachers, teacher educators, and researchers. In the second section, online and blended Professional Development (PD) carried out in countries such as the United States, Singapore and Germany are used to show the potential of informal (bottom-up) initiatives, which allow arts and music teachers to interact not only with their peers, but also with teachers specialized in other subjects, PD providers, and professional associations. The third section recommends policies to enhance arts and music teacher PD at large, and in particular the research-practice-policy pipeline. We argue that policies should focus on actionable knowledge within shared spaces and ecological frameworks of learning. The article concludes by proposing additional examples of anti-isolationist policies in arts and music education.