The rise of digital communication environments may prompt shifts in scientists’ communicative roles, particularly in the context of socio-scientific issues (e.g. climate change, Covid-19), where scientists can gain greater visibility among the public. This chapter sheds light on communicating scientists as embodiments of trustworthy knowledge and their (new) roles in digital communication environments. Scientists’ roles can be integral to their engagement with the public, because the underlying values, motives, and perceived expectations can determine scientists’ actual behaviour. While role theory can provide a useful structure to capture scientists’ communication, their communicative roles have barely been studied empirically. This chapter introduces an analytical framework for examining scientists’ communicative roles in digital communication environments from different perspectives, applying the journalistic role concept (Mellado, 2020; Mellado et al., 2016) to communicating scientists. By way of illustrating the application of the journalistic role concept to scientists, selected results from a case study on visible scientists’ role performance on Twitter/X during the Covid-19 pandemic are presented.