Haidee’s research focuses on language variation and change in contact settings, with an emphasis on both the psycholinguistic and social conditions of language contact. Within this framework, she studies translated language, World Englishes, and learner language. Her most recent work is at the interface of linguistics and digital humanities, and focuses on language change in parliamentary discourse across varieties of English, and the role of language mediators like editors and translators in this process.

Haidee is the editor-in-chief of the journal Target: International Journal of Translation Studies. She is an international staff member of the Centre for Translation Studies (CETRA) at KU Leuven, and a member of the international Thematic Network on Empirical and Experimental Research in Translation (TREC), the Interdisciplinary Research Network in
Translation Studies and Linguistics (InTraLing), and the ICLA Research Committee on Language Contact in Literature: Europe. She is a contributor to the grammar of Afrikaans for Taalportaal, and has worked in several projects in the framework of World Englishes, including the Varieties of English in the Indo-Pacific: English in Contact (VEIP-EIC) project.

Haidee also holds a position as honorary professor in the research focus area Understanding and Processing Language in Complex Settings (UPSET) at the North-West University in South Africa.