Haw. Rev. Stat. § 255D-4
The department with the concurrence of the legislature may enter into the streamlined sales and use tax agreement with one or more states to simplify and modernize sales and use tax administration to substantially reduce the burden of tax compliance for all sellers and for all types of commerce. In furtherance of the agreement, the department may act jointly with other states that are members of the agreement to establish standards for certification of a certified service provider and certified automated system and establish performance standards for multistate sellers. The department may take other actions reasonably required to implement this section. Other actions authorized by this section include but are not limited to the adoption of rules not subject to chapter 91 and the joint procurement not subject to chapter 103D, with other member states, of goods and services in furtherance of the cooperative agreement. The department, or the department's designee, may represent this State before the other states that are signatories to the agreement.
HRS § 255D-4