The best definition of the word culture (workplaces included) that I’ve heard is that it’s how people behave when nobody is watching.

The introduction of Chapter 13, Project Stakeholder Management, as a new knowledge area was perhaps the most significant change between the 4th and 5th editions of the Project Management Institute's PMBOK Guide. While stakeholder management was very present in the PMBOK Guide 4th edition (primarily in the Communications Management knowledge area), the significance of this addition is that it raises the importance of engaging stakeholders to the same level as all of the other PM knowledge areas.  <<Article>>