The rhetoric abounds concerning the types of effective, high trust, interactions that should exist for a school governing body. In practise, however, such interactions are often difficult to define, establish, maintain, and sustain. The study reported on in this paper attempted to identify interactions linked to perceptions of high trust via a "success case study" examination of characteristics of productive and defensive strategies utilised by three New Zealand (NZ) primary level school governing bodies (Boards of Trustees) that had been identified as being effective. All three schools exhibited strong productive interactions where open, evidence based, discussions predominated in a dialogue (informed debate) context. The case studies provide a set of indicators that illustrate the detailed strategies that can be employed that lead to effectiveness and high trust. The initial section of the paper backgrounds the governance context in NZ schools where locally elected Boards of Trustees (hereafter described at Boards) hold high levels of responsibility and autonomy for strategic and policy decisions. Following this, the link between effectiveness of Boards and productive interactions is established. The theoretical underpinnings of defensive and productive approaches are explored prior to a description of the success case methodology employed to examine the interactions of effective Boards. The results of the three case studies are presented and overall conclusions drawn. The final part of the paper explores an approach to adopting the type of productive values and strategies that the case studies highlight. (Contains 2 tables.)