These are the different ways that software can be shared between governments.
Multiple stakeholder agencies work together (either informally or with an MOU) on development from the start, with each agency contributing in the form of staff/contractor time. This may be reused as SaaS or as executables/source code.
Multiple agencies are members of an organization, and that organization performs development work via direct hires or contracting. Those agencies may contribute financially or there may be external funding (e.g., from a higher level of government or from a foundation). The organization may have been created expressly for the purpose of this software collaboration, or it may be an existing organization. In this scenario, software may be reused as SaaS or as executables/source code.
An agency builds software and releases the software or source code publicly, and other agencies then use that software. The software continues to be housed by the original agency.
An agency builds software and releases the source code publicly, and employees of other agencies contribute their modifications. It may continue to be housed by the original agency, or it may transition out to be community supported.
A non-government organization has created open source software, and it becomes used within government agencies, which then make contributions to the software so that it can better serve their needs.
A parent government builds software and shares it with child governments (e.g., a state provides it to counties) as SaaS or as executables/source code.
An agency builds software that is in the public domain, a private organization takes it over and redistributes it, other agencies then purchase/reuse it via that private organization.
An agency hires a vendor to build custom software for them, but the vendor retains copyright. The vendor then resells the software to other agencies, who may not be aware that the software was built for another state or territory. This isn’t strictly “cooperative” or “sharing,” but it does provide some of the same benefits as the other models, and is included here for completeness.
Example: Deloitte’s HealthInteractive