Teachers’ collegiality is becoming an increasingly important component of teachers’ professional development programmes that are geared at improving students’ learning. Studies have shown that, through collaboration, teachers can learn from one another and develop professionally. This study investigates the extent to which true collegiality exists in teacher design teams in the Netherlands and in Tanzania. It specifically investigates the ways in which teachers establish collegiality in schools and the influence of education authorities (inspectorates, school management and policy makers) in teachers’ decision making in the design teams. It also investigates how varying interests, values and attitudes of teachers are accommodated in the design teams. A convenience sampling approach was used to recruit eight participants: four from the Netherlands and the other four from Tanzania. Through interviews with the participants it was revealed that almost all design teams were formed through external influences, such as research teams and school management. In both cases (the Netherlands and Tanzania) educational authorities such as the government, school inspectorate systems and the school management had a direct influence on the teachers’ participation and decision making in design teams. Almost all teachers’ collaboration groups had some elements of contrived collegiality, although the magnitude differed from one collaborative team to another, as well as from one country to another