D.C. Mun. Regs. tit. 17, r. 17-3209
For the purposes of this chapter, the term "practice of interior design" means providing or offering to provide consultations, preliminary studies, drawings, specifications, or any related service for the design analysis, programming, space planning, or aesthetic planning of the interior of buildings, using specialized knowledge of interior construction, building systems and components, building codes, fire and safety codes, equipment, materials, and furnishings, in a manner that will protect and enhance the health, safety, and welfare of the public whether one or all of these services are performed either in person or as the directing head of an organization. The practice of interior design does not include the practice of architecture, as defined in D.C. Official Code § 47-2853.61.
This chapter shall not require a license for, or restrict or prohibit an individual from engaging in, any activity or service described in § 3209.1 of this chapter, if the individual is a licensed architect engaged in the practice of architecture pursuant to the laws of the District of Columbia. An individual licensed as an architect may not utilize the title "Interior Designer" unless the individual is also a licensed interior designer.
For the purposes of this chapter, the issuance of a building permit by the Department under the authority of the District of Columbia Construction Codes shall not constitute a license to engage in an activity or service enumerated in § 3209.1 of this chapter.
D.C. Mun. Regs. tit. 17, r. 17-3209