Key people for your big day -- you need to decide who they are as early in your wedding planning process as possible, preferably you would decide these people before the wedding planning process starts.

Controller
This is the person who has the final say in decision making. Keep in mind that this person does not need to make 100% of the decisions, but will be the determining vote when decisions are being made. Usually this is the bride or groom or one of their parents. 

Manager
This is the person who will be running the events the ‘day of’ and handling any last minute changes, questions, dramas. This should not be anyone who is in the family or in the wedding party or the MC of a main event, it should be an organized person who knows the Controller’s intentions and will try his/her best to execute them. Often it is a close family friend or a wedding planner.