Waveguide-based evanescent Raman sensors are an attractive chemical-detection technology due to their compact format, increased signal over micro-Raman spectrometers, and nanoscale surface sensitivity. To improve the device’s performance, herein we experimentally demonstrate strategies to increase the efficiency of waveguide-based evanescent Raman sensors over the state-of-the-art silicon-nitride devices by more than an order of magnitude. First, we use pumping at visible wavelengths (532 nm versus 785 nm, which is commonly used) to exploit the Raman cross-section’s λ–4 dependence. Second, we use titanium dioxide (TiO2), which combines comparatively low visible background luminescence with a high refractive index to concentrate light near the waveguide’s surface. These visibly pumped TiO2 sensors display >50× more Stokes signal per input pump power over that of silicon-nitride devices. Lastly, we explore ring resonators and observe on-resonance Stokes emission with peak rates >30× higher than an equivalen...