Purpose: This conceptual paper aims to explain how "project management centres of excellence (CoEs)", a particular class of knowledge network, can be viewed as providing great potential for assisting project management (PM) teams to make wise decisions. Design/methodology/approach: The paper presents a range of knowledge network types and classifies them into a matrix using dimensions of social capital formation and learning levels. Examples were used of each identified type, drawn from the literature, to illustrate and clarify the capability maturity levels, from ad hoc isolated communities of interest to integrated and strategic CoEs that serve to propagate and transfer knowledge about an organisation's advanced project management skills and tools. Findings: The paper presents a useful framework for understanding this evolution and argues that CoEs can optimise, help coordinate and enhance the effectiveness of a range of knowledge networks operating within an inter-organisational or intra-organisational project team. Originality/value: The framework: facilitates PM organisational leaders to understand knowledge networks from a social capital formation and learning organisation perspective; highlights limitations of each of the identified knowledge network types from this perspective; and challenges PM leaders to strategically create and maintain a workplace environment that both encourages PM best practice and maximises organic learning development from which knowledge networks spring. PM leaders need to realise that sustaining CoEs is highly corporate resource intensive, however, derived benefits can include reduced wasted effort, poor project outcomes and increase organisational learning that facilitates continual PM process improvement. The framework provided here helps to justify that commitment.