The research explores student voice in the process of designing schools, using a case study of a Buildings Schools for the Future (BSF) One School Pathfinder project, 2005 – 2007. The suggestions made by the students during the design development were compared with those raised by the staff and parents to discover if the student voice brought anything different or unique to the project. Comparisons were then made with the Student Council’s contribution on projects at two schools local to the case study school. To explore the contribution made by ‘non traditional students’ a similar exercise was conducted in a Pupil Referral Unit (PRU) with students who had been expelled from mainstream schools because of behavioural issues. Group interviews and focus group feedback from students at the case study school, from different stages of the design process were examined to assess the impact the student voice may have had on the completed design. Interviews were conducted with members of the design team at the case study school to establish how much impact the student voice was perceived to have had on the completed design compared with the voice of others, whether it brought innovation to the design and if involvement in the project had an impact on the students. Comparisons were then made with interviews held at a second BSF Pathfinder in a neighbouring Local Authority and the findings submitted for peer review. The findings appear to demonstrate that there is very little difference in what the student voice contributes; across schools and across time, the student voice is consistent and predictable. The impact of the student voice was found to be minimal compared with the impact of others. The process of involving students in the design process was however felt to benefit the students and the design process. Finally suggestions are made as to how the involvement of student voice can be improved, and moved from a consultation process to one of collaboration in the future; for ways to address the balance of power within the design team and for further areas of research.