The complex and multilayered world of the 21st century no longer appears to support the conventional idea of great leadership being the result of the efforts of a single individual. Indeed the idea of learning communities, where educators are seen as active participants in developing educational procedures at all levels and are at the centre of the educational change process, is now widely promoted. In order to succeed in the process of building leadership in a learning community, relationships and communication are seen as key aspects, with some authors promoting dialogue as integral to the process. This small-scale qualitative study uses a semi-structured interview process to gather data from eight educational leaders, working within New Zealand, who had participated in extended professional dialogues at the International Leadership Institutes (ILI) in the Waikato. The study explores the influence of that process on their professional capabilities as leaders and considers the nature and extent of their learning. It also looks at how dialogue continues to impact on their leadership practice after they have experienced repeated ILIs. Theoretical and empirical research suggests that professional dialogue promotes critical thinking and inquiry through a process of consent and dissent to achieve a co-construction of knowledge. Dialogue enables a group to explore why certain presuppositions, ideas and beliefs exist within the group and to reveal why they are interacting in certain ways. It is a process that observes, collectively, how hidden values and intentions can control our behaviour and seeks to surface these in order to construct new ways of interacting and new knowledge. This study found that by working in groups through a process of dialogue, not only did the group extend its capabilities beyond that of the sum of the individuals, but that self awareness and understanding developed and continued to have an effect on thinking and behaviour long after the actual ILI was completed. The findings are of use for those who seek to use dialogue as a successful communication tool in their own leadership contexts. While the findings are specific to the program under investigation, including its structure and local, historical context, they can be related to the wider world of education which asks for all involved to be focused on learning. How we learn and how we learn together is a major concern of leaders in learning. This study calls on educational leaders to explore dialogically how to enable their colleagues to be more successful in the work at hand and how to develop collective thinking, closer relationships and an ongoing way to approach diversity and change in our society.