Since its emergence in the 1960s, English for Specific Purposes (ESP) has been a dominant subfield in language education and English language teaching. The mainstream ESP literature appears to be linguistic-oriented with less attention directed towards ESP teachers. Responding to the calls for more ESP teacher research, this systematic review aims to be a substantial starting point in scrutinising research on ESP teachers published from 2010 to 2022 in the Scopus-indexed journals to frame current research foci, explore existing pedagogical collaborations, and propose suggestions regarding the issue of sustainability. Thirty-seven empirical studies were initially short-listed, of which thirty-two were analysed. A synthesis of ESP teacher articles yields seven lines of research: teachers' perceptions and beliefs, teachers' identity development and agency, perceived challenges and needs, collaborative practices, teaching and innovation, teachers' knowledge, and technology in ESP. Two distinctive types of collaboration to effective instruction across contexts are illustrated. Drawn from the twelve years of research, the sustainability in ESP is presented to depict pedagogical, administrative, and policy implications. Last, future research directions are also proposed.