The Greek philosophers said nothing lasts forever, except change. Yes, people move on, and businesses and their brands evolve. Sometimes the grass appears a shiny, brighter shade of green somewhere else. But when you take time to nurture good relationships with your design consultant, if you get the balance right, there will be time to do some extraordinarily good work.
It really comes down to being enthusiastic, being ready to listen and learn, applying your knowledge, standing up for what you know to be true, remaining honest, sharing what you know, keeping your mind open to alternatives and above all, making every piece of work count.
Have fun out there!