More than 25% of the master's degrees in Denmark are taught using English as a medium of instruction (EMI), but not all university lecturers feel they have the appropriate academic English proficiency to meet the standard required. Based on interviews conducted at the Copenhagen Business School (CBS), this article sheds light on the challenges faced by a selection of these lecturers. The interviews formed part of the project "Students' Perceptions of the English of Academics," which examines the use of EMI at CBS. Audio recordings were made of 33 lecturers. Questionnaires were distributed to almost 1800 students on a range of issues, including the lecturer's English proficiency. The lecturers themselves also completed a questionnaire. Subsequently, 17 of them were interviewed, five of whom belonged to the group with the weakest skills. Inspired by a categorisation used by Marschan-Piekkari, Welch, and Welch for their recommendations for managing English as a corporate language, the literature review in the present paper discusses university language management under the headings of staff selection, training and development, international assignments and performance appraisal. The insights gained from the interviews address issues such as attitudes to EMI policy, experience with EMI teaching, student evaluations and support.