Webinars are a powerful digital tool for learning about sustainability in a global context. The implementation of different technologies in teacher education, such as webinars, is becoming indispensable due to digital transformation and internationalisation processes. In this context, digital competences are described as key to quality education and a sustainable future. In teacher education, there is little evidence on how digital tools can be used for learning about sustainability. Based on the "Teach4Reach" project, a two-year international study on the Sustainable Development Goals in teacher education describes learning experiences in webinars by presenting selected vignettes. The question is how digitisation can support learning on sustainability in a global context of quality education. We conclude that webinars are a digital tool that supports knowledge building and collaborative learning in an international context but that their specific properties need to be recognised. The vignettes exemplify various challenges and opportunities presented by webinars, such as the fundamental role of facilitators, ease of access to the online environment, different behaviours of participants and unknowns about the learning outcomes.