Summative and formative assessment are a core part of the teaching and learning process. A broad range of assessment methods is desirable to give a true measure of students' understanding and progress. However, research indicates that proctored, closed-book, summative assessments are traditionally favoured by university mathematics lecturers. In March 2020, assessment practices had to be abruptly reconsidered by the majority, midway through semester. An online survey of how mathematics lecturers adapted to emergency remote teaching was conducted in June 2020, with responses from 257 teaching staff in 29 countries. In this paper, the authors detail how assessment in mathematics was undertaken, remotely and virtually. We investigate how lecturers dealt with an enforced move away from traditional closed-book, highly weighted, proctored, in-person examinations, and how satisfied they were with their eventual assessments. We explore lecturers' perceptions of the impact the changes had on grade distribution during this unique teaching period. Finally, we report on whether their approaches to teaching the same modules in the future will change as a result of their experience of emergency remote teaching during the COVID-19 pandemic.