In this article, we report on a mixed-methods study which investigated teachers' attitudes towards and experiences with teaching environmental issues within their ELT classes. Given the rising importance of ecoliteracy and its inclusion as a transversal learning objective for all subjects in many national state curricula, it is critically important to understand how ELT educators can be best supported in addressing simultaneously both linguistic and environmentally related teaching goals. Data were collected via an online international survey (n = 91) and a series of in-depth, semi-structured interviews (n = 5). Analysis of the data reveals the specific strategies ELT teachers employ when integrating environmental issues alongside linguistic issues, what their motivations for doing so are, what resources and materials they use, and what challenges they face. The article offers valuable insights into the factors that facilitate the sustainable and effective teaching of both language and environmental issues in diverse ELT contexts across the globe.