We propose to expand the analytical capability of the University of California, Santa Barbara Marine Science Institute (MSI) to include nitrous oxide (N20) isotopomer and compound-specific isotope analyses (CSIA) through the acquisition of a stable isotope ratio mass spectrometer and three supporting peripherals. CSIA has largely replaced bulk measurements at the forefront of isotope ecology and biogeochemistry, yet these analyses remain isolated in relatively few laboratories. UCSB has tremendous research strength in the environmental sciences, particularly marine science, including multiple researchers with deep expertise in isotope approaches. The new instrumentation would arrive in a research environment ready to capitalize on its capabilities. The MSI Analytical Laboratory, where the new instrumentation would be housed, is a recharge facility with a 45-year history of successful operation staffed by two full-time professional technicians. This acquisition would catalyze cross-department interactions by facilitating a space where faculty and students from across campus using similar methods can interact without being siloed by departments.