Coupled channel analyses favor the existence of only one broad ${}^{}1{}^{-+}$ isovector state consistent with ${{\mathit \pi}_{{{1}}}{(1600)}}$ in the $1400 - 1600$ MeV region. Accordingly, the ${{\mathit \pi}_{{{1}}}{(1400)}}$ entries of the previous Reviews have been moved into this section. See the review on "Spectroscopy of Light Meson Resonances."