Interior designers, or decorators seem to be a dime a dozen. Everyone and their mom seems to think that interior design is simply a gift, and that anyone can design without any formal training. That may be the case for some, but many interior designers take themselves more seriously than that.
For example, Kirstin Havnaer from Hearthstone Design LLC, has her MBA in Business, and also Bachelor degree in psychology. She is also achieved AKBD certification (Associate Kitchen & Bath Designer), graduated from Western School of Feng Shui, Heritage School of Interior Design, and completed studies with the IACC (International Association of Color Consulting). She is an over-qualified interior designer to say the least.
With that said, her education in Psychology is particularly beneficial to help her clients through the sometimes difficult emotional changes that happen through a remodel or design change.