In this chapter, we set the context for how teachers can use the CLLP and its resources sustainably by introducing why it is important for teachers to engage in long-term collaboration to implement the core aims and themes of DIALLS in a meaningful way. In the following chapter, we will introduce research on the opportunities and obstacles of online collaboration among teachers. Considering that the goals of DIALLS deal with issues of living together, social responsibility, and sustainable development, we will emphasize how effective online collaboration not only among students but also among teachers can help make DIALLS have a long-lasting impact that shapes the educational future of Europe. Thus, we will emphasize how to promote a long-lasting community of practice for DIALLS teachers and how this community may enable them to become professional DIALLS teachers.