Answer : Interior designer is a profession in the field of interior design and draws up contract designs for new buildings and develops plans and specifications for alterations to existing buildings. Interior designers usually specialize in certain design fields such as residential, commercial or industrial. What education do you need to become an interior designer? You'll need a high school diploma, formal training in an accredited 4-year program - such as at a community college or university with an interior design program - which will take approximately 3 years to complete. After completing this course, the student would then acquire their certification from one of two national organizations: The National Council of Interior Design Qualification (NCIDQ), or Association of Collegiate Schools of Architecture (ACSA).