Finding out what's beneath you is always a good idea before digging a hole in the ground, especially a large one. Similarly, for medium to large organisations, it's difficult to instinctively know how your whole system of processes is interlinked and what information is flowing around. If you're thinking of making any process improvements, it's important to know this and you'll need a map. Unfortunately, Professor Google can't help with your organisation's specific map but there is a technique that can. It's called a Linkage of Process and it's quick and easy to create.
It simply depicts an organisation in terms of its significant processes and the linkages between them. There are no definite rules. The processes may be shown in isolation or grouped into sections, such as Driver, Core and Support and then further into Departments Customers and Suppliers. The linkages may be marked up with information flows and quantities, or whatever is relevant to a particular need. When it's complete, you may be surprised to see how interlinked your organisation is and how any changes in one area may affect other areas, both internal and external. It may just prevent making an expensive mistake.