Teachers report that there are an increased number of students engaging in persistent antisocial behaviour in their classrooms. Teachers need to identify these students early because if there is early identification then there is the potential for early intervention, which in turn may prevent negative long-term outcomes for these students as well as long-term costs to society. The aims of this study were (1) develop a psychometrically sound, cost effective, three-step multiple gating behaviour screening procedure that teachers could use in their kindergarten/classroom so that they could identify those students at-risk of antisocial development, (2) examine if the third gate of this procedure was necessary for the accurate identification of these students, and (3) could such a screening procedure be adapted for classroom teacher use in New Zealand kindergartens and schools. Forty eight teachers from three kindergartens and 10 primary/intermediate schools volunteered for the study, of which 34 teachers completed all three gates of the screening procedure. Results indicate the three gate screening procedure was easily adapted for kindergarten and classroom use with, at Gate 3, teachers’ self-recording 30 direct observations of a nominated and control student during their normal teaching lesson with good accuracy. All three gates were effective in identifying those students at-risk of antisocial development but Gates 1 and 2 were the most effective in terms of accuracy, time and resourcing. The teachers found the three gate procedure manageable, required very little training and did not interrupt classroom routine or schedules. The implications of these findings are discussed.