The National Science Foundation's Nanoscale Interactions program is seeking proposals for exploratory research projects that advance the fundamental and quantitative understanding of the interactions of nanomaterials and nanosystems with biological and environmental media. The program is particularly interested in research areas such as characterization of nanomaterial interfaces, development of predictive tools for nanoscale phenomena, examination of the transport and impact of nanostructured materials, simulations of nanoparticle behavior, and investigations of quantum vibronic and spin phenomena. Proposals should address the novelty and potentially transformative nature of the proposed work, as well as its importance in terms of engineering science and potential impact on society or industry. Single-investigator award budgets typically include support for one graduate student and up to one month of PI time per year, with award durations generally up to three years. Faculty Early Career Development (CAREER) program proposals, which have a five-year award duration, are also strongly encouraged. The program accepts proposals on a rolling basis, and PIs are encouraged to discuss their requests with the program director prior to submission, particularly for RAPID, EAGER, and GOALI proposals.