Innovation in and adoption of open hardware practices for scientific instrumentation and apparatus are being held back by the lack of widely-accepted standards in the description and versioning of open hardware projects. Metadata standards, in particular, are essential infrastructure to enable discovery and collaboration. A typical open source hardware project can combine instructions for 3D-printed components to be built locally along with a heterogeneous range of premade components (with different degrees of quality control) from a number of suppliers, along with any number of software programs used to control the device. At the moment, much open source hardware is in the “you can find documentation on my website” stage of maturity, where documentation and assembly instructions are idiosyncratic to the individual creator, and collaboration beyond small, local teams is more or less impossible.This grant funds Andrew Lamb, the founder of the Internet of Production Alliance, in a project to establish five families of metadata standards for open hardware: Designs and Documentation; Machines and Tools; People and Skills; Materials and Components; and Contracts and Business Models. These five standards are at different stages of maturity and build on each other: the first two (Open Know-How and Open Know-Where) have already been developed and activity will primarily focus on broader adoption and maintenance; the next two will be actively developed and launched over the course of the two years; and the last will be scoped for future development.