Classroom management skills are essential for effective teaching and consequently form an integral part of undergraduate teaching degrees. Self-efficacy in classroom management influences an individual's willingness to undertake specific actions and their perseverance in the face of difficulties in executing these actions. In order to track the progress of pre-service teachers' self-efficacy in classroom management, an easy to administer Classroom Management Self Efficacy Instrument (CMSEI) was developed and piloted with a third year cohort of pre-service teachers. This article reports on the psychometric properties of the CMSEI as determined through a Rasch analysis. The analysis supports the Classroom Management Self Efficacy Instrument (CMSEI) as an accurate and internally consistent, unidimensional scale for use with undergraduate pre-service teachers.