We report the design and implementation of antiresonant reflecting optical waveguides (ARROWs) in the InGaAs/InP system. Large modes are achieved with losses of 4dB/cm and vertical diffraction FWHM OF 23° at 1.51μm. Since light is confined in the lowest-index layer rather than the highest-index layer as in conventional waveguides, these guides offer important new design freedom for integrated-optics applications.