We agree that it would be useful to have a mechanism for sharing and including RuleSet libraries. Some questions we will need to consider: Are RuleSets the only thing we'd want to share? What if a RuleSet references something else? How should these FSH libraries be packaged? How should these FSH libraries be shared / distributed? How should these FSH libraries be scoped when used in a project? As the commenter suggests, we may want to consider using FHIR Library as a mechanism for representing FSH libraries / files / definitions. If so, we should see if leveraging CRMI might answer some of the questions above. We've also considered allowing FSH projects to import other FSH definitions from GitHub repos. We will consider this for future versions of FHIR Shorthand.