Many people are confused about what interior design and interior decorating is. Here are some basic differences between interior designers and interior decorators.
The main difference is an interior designer must have an accredited degree. In fact its illegal to call yourself an interior designer if you don't have a degree in interior design. Interior designers must work alongside architects and other design professionals in many cases so a degree cannot be ignored.
Interior decorators design and arrange elements of an interior space. Interior designers actually design the space interior decorators work in.
You can read more about the difference between interior decorating and interior design.