Raman scattering from a single ferroelectric-ferroelastic domain wall in Gd 2(MoO 4) 3 has provided direct experimental evidence for a thick domain wall (thickness > 0.8 μ). Direct observation in a polarizing microscope yields a maximum value of 3μ, thus bracketing the thickness between 0.8μ and 3μ. The scattering from the wall is observed to be typical of the high-temperature tetragonal phase.