With the discovery of a RNA nano-scaffold that remains unusually stable in the body, researchers have overcome another barrier to the development of therapeutic RNA nanotechnology. The nanoparticle, constructed from a three-way junction (3WJ) motif of packaging RNA (pRNA) molecules, can serve as a platform for building larger, multifunctional nanoparticles — which can then be injected into the body to deliver therapeutics to targeted cells.