Background/Question/Methods Natural history collections are rapidly being recognized as critical resources for understanding ecological change. Archival specimens allow researchers to directly observe populations and communities over otherwise inaccessible spatial and temporal scales. However, the sampling strategies employed in building natural history collections were not historically designed for the purpose of monitoring and forecasting change and can often be difficult to reconcile with population, community, and ecosystem-level patterns and processes. Therefore, new infrastructure is needed in the form of biorepositories, defined here as biocollections with the explicit purpose of optimizing sample composition and processing to monitor ecological and evolutionary change. Biorepositories are charged with preserving (and redistributing for research) unconventional sample types that represent physical records of within and between species diversity, collected through systematic resampling in concert with fine-scale environmental data collection. Results/Conclusions The National Science Foundation’s National Ecological Observatory Network (NEON) Biorepository is an early test case of this collections concept. The samples housed at the NEON Biorepository reflect the within species variation, community composition, and ecosystem properties of NEON sites over time and are preserved with methods that maximize their long-term research potential. However, the NEON Biorepository consists of samples from a limited number of geographic sites and taxonomic groups, and temporal sampling is shallow at this early stage of the project. We visualize and quantify how the unique features of natural history collections and the NEON Biorepository can complement each other to maximize our ability to detect signals of biological change. Finally, we discuss ongoing and potential future work leveraging NEON Biorepository samples to study macroecology, population structure, microbial ecology, ecosystem ecology, and species interactions.