Project management is well served with bodies of knowledge, methodologies and other guides that give those new to the discipline a starting point for learning. They also provide useful points of reference for experienced practitioners and a framework for implementing project management across an organisation.
There are three things that have always frustrated me about these publications.
Firstly, none of them cover the whole picture. They tend to focus on either knowledge, method, competence or maturity. Some address two of these but rarely three and never all four.