The joint Australian Association of Mathematics Teachers AAMT/Monash University project 'Excellence in the teaching of mathematics: professional standards project' has been working with teacher focus groups in four states to try and build a picture of what mathematics teachers believe represents excellent teaching. This paper discusses the second aim of this project: to develop an assessment scheme and protocols for certifying this excellence. Topics discussed are developing ways to assess excellence, looking at an American model of assessment - the National Board for Professional Teaching Standards (NBPTS), and other models for standards of excellence in teaching.