I would add to this, contingency plans. At the beginning of each project we usually have clearly defined plans with assigned responsibilities and then the inevitable happens when something unforeseen happens that falls out of the detailed plan and its unclear of what the next steps would be and who is responsible to address. This falls in line with your #4 Management of Scope and to avoid scope creep, the uncontrolled growth of the scope of the project when the project isn’t properly defined, documented or controlled.