Ecologists are increasingly adopting and developing new isotopic, molecular, and spectroscopic techniques in truly interdisciplinary ways to gain insight into ecological and biogeochemical processes. Recent technological and methodological advances have improved our ability to characterize the chemical composition of organic matter in small samples, rapidly, and in situ. We invite authors to present ecological research that has benefited from the application of new isotopic, molecular, and spectroscopic techniques. Particular areas of research that have greatly benefited from new methods are the study of carbon and nitrogen cycling in soils and aquatic environments, and the decomposition and turnover of plant and microbially-derived material. The goal of this session is to promote interdisciplinary collaborations for the increased application of new methods to improve our understanding of ecological and biogeochemical processes. Some of the methods that will be presented by invited speakers are: compound-specific isotopes, pyrolysis gas chromatography-mass spectrometry (pyGC/MS), 15N- and 13C-nuclear magnetic resonance (NMR) spectroscopy, nanoSIMS (secondary ion mass spectrometry), fluorescence and quantum dots. We welcome contributions presenting other methods not listed here, but of general interest to ecologists.