Empirical research into the expectations of interpreters and end-users indicates that the former are generally more demanding, but that pleasant voice and/or intonation are not seen as important criteria in the assessment of interpretation quality in either of the two groups. Drawing on this research, and on the presuppositions that had guided other empirical work on user expectations of quality in interpreting, the author sets out to achieve the following objectives: 1) to determine the quality expectations of a specific group of end-users of simultaneous interpretation, 2) to determine the quality expectations of professional interpreters, both in their role as speakers and in their role as listeners. The study also tests the perception of monotonous intonation; it was the idea to analyse the extent to which monotonous intonation in simultaneous interpretation might affect the receptor’s assessment of the original discourse, and to determine how monotonous intonation may affect the evaluation of the original speech by users and interpreters.