Wikipedia describes project management as follows
Project management is the discipline of planning, organizing, securing, and managing resources to achieve specific goals.
What it does not do, is define what those resources are.
Typically, people think of project resources are being Human resources and Capital resources, such as
But lets add number 6 - Knowledge - an Intellectual resource.
I think knowledge is often ignored as a project resource, as it is assumed that the people hired onto the project team will bring knowledge with them, but those of us who work with KM know that knowledge can be treated independent of the people. Knowledge Management and HR management are not the same.
That's why a project needs to treat knowledge as a resource, and manage it as such, through the use of a project Knowledge Management plan, and through the application of processes such as Peer Assist and After Action review.
(for more detail of KM in projects, see here)