We present a spectroscopic analysis and laser characterization of optically written waveguides in neodymium-doped gallium lanthanum sulphide (Nd3+-Ga:La:S) chalcogenide glass. Uniform channel waveguides were fabricated in Nd3+-Ga:La:S by exposure to radiation from a focused uv-laser beam (λ=244nm), producing a refractive index change Δn ~ +10^−3. The observed laser performance and fluorescence decay were in good agreement with values calculated from a spectroscopic analysis of 85μs for the 4F3/2 lifetime and 5.9 x10^−20cm^2 for the emission cross-section at 1075nm. Low threshold laser operation with emission at 1075nm and a slope efficiency of 17% is demonstrated. The active device is spatially single-mode and exhibits up to 8.6mW output power and propagation losses of <0.5 dB cm^−1. Waveguide fabrication, photoinduced effects and optical characterization in terms of spectroscopy, laser performance and device attenuation are discussed.