Grand challenge questions requiring a deeper understanding of biological systems and technologies are as diverse as life itself. Understanding the complexity of living systems and their interactions with human-derived products and processes, ensuring the safe, ethical and equitable access to and co-generation of knowledge and products, requires the sustained development of technologies, sophisticated instrumentation, workflow pipelines and their automation, and advanced computing that are beyond the capabilities found in the laboratories of individual investigators. Broad access to these tools, workflows, processes, and knowledge bases in a facility that is capable of bespoke design and process scale-up, in response to user needs, is essential for addressing grand challenges and translating the knowledge created into applications for the bioeconomy, to meet societal and national needs. BioFoundries is an infrastructure program from the National Science Foundation (NSF) that is designed to accelerate advances in the biological sciences, chemical biology, biotechnology, and bioengineering via access to modern infrastructure, technology, and capacity. BioFoundries will provide the intellectual, technical, digital, and physical frameworks needed for tight integration of technology innovations and applications with foundational interdisciplinary research and training, by: serving as access points for new biological technologies, workflows, processes, automations,and knowledgebases to enable transformative discoveries; catalyzing new innovations and transformative discoveries by supporting in-house and external user-initiated research programs that take full advantage of technological and methodological advances; continuing to develop novel technologies, workflows, processes, automations,and knowledgebases that are both forward-looking and user-responsive; increasing the reproducibility of life science discoveries and data and knowledge sharing capabilities; training the next generation of the scientific workforce; and facilitating pathways to translation. Leveraging lessons learned from existing national and international biofoundries, NSF encourages researchers to consider a diversity of models (centralized, distributed, consortium) in the design and implementation of BioFoundries. Each BioFoundry should enclose a scientific ecosystem, that includes in-house research scientists across all relevant disciplines supported by NSF, technical staff including cyberinfrastructure experts, external users, and other contributors who, collectively, form a community of practitioners and share tools, reagents, workflows, software, samples, and data. Knowledge sharing should be a central tenet, designed to strengthen collaborations among researchers and enable them to work in new ways and to foster new modalities of research and education/training, for the purpose of accelerating discovery and advancing development. BioFoundries should promote diversity, equity, inclusion, and accessibility in their in-house programs and external user programs. BioFoundries should also promote new avenues for translating such knowledge and technology broadly in ways that benefit society.