Resumen: The multifaceted character of environmental discourse becomes evident on social media, where non-governmental organisations (NGOs) engage in public environmental discourses. Focused on X/Twitter for environmental purposes, this paper investigates engagement as an interpersonal phenomenon comprising two dimensions: self-presentation and audience projection. It qualitatively and quantitatively analyses 100 X/Twitter posts from WWF and Greenpeace (50 per account) with the tool NVivo 14. Findings reveal how the NGOs rely on verbal (self-mentions, lexical items) and non-verbal resources (emoji and multimedia elements) to present themselves to their audience, whilst exploiting verbal resources (second-person pronouns and directives) to construct their audience. Results underscore how NGOs leverage X/Twitter to assert their own legitimacy and that of their audience as integral members of the environmentalist community. Idioma: Inglés DOI: 10.1075/ld.00189.san Año: 2025 Publicado en: Language and Dialogue ISSN: 2210-4119 Tipo y forma: Artículo (PostPrint) Área (Departamento): Área Filología Inglesa (Dpto. Filolog.Inglesa y Alema.)