Every recommendation above assumes a place where Horizon 3 work can actually live. Section S1 described why that place does not exist by default: the current environment absorbs whatever is dropped into it. Drop a cucumber into brine and you get a pickle, every time, and the procurement rules, decision chains, capacity constraints, and incentives of the current environment pickle transformation initiatives just as reliably, regardless of technical merit.
The countermeasure is a protected environment: a bounded initiative operating under deliberately different conditions, with expedited decisions, dedicated capacity, and a procurement and funding pathway matched to learning, sustained long enough to prove that a new way of working produces better outcomes. This is the state-side counterpart of the CMS Horizon 3 function recommended in S1: CMS makes protected conditions authorizable through APD pathways and waiver mechanisms that grant relief from default conditions, and states operate within them.
The unit of work inside a protected environment should be an end-to-end slice of real service delivery, because the slice is where everything this response recommends actually happens. A narrow slice run end to end forces every function it touches, policy, security, privacy, procurement, operations, and technology, to work in a new way at small scale. People do not have the future state described to them in a change management communication; they experience it, in miniature, with real citizens served. Staff develop modern skills by shipping inside the slice. Consent, privacy, and security practices get designed by the people who must navigate them. Organizational change facilitated any other way is a presentation; change facilitated through slices is a capability. Importantly, thousands of tiny failures generate learning that prevents future catastrophic ones.
Slices are also the honest answer to the harmonization question this RFI asks. Aligning MES standards with broader HHS and ONC interoperability rules on paper is easy; harmonization in running systems is the only kind that matters. Run slices that cross domain boundaries, Medicaid eligibility touching human services data, public health reporting, behavioral health, and let the standards that work emerge from what those slices teach. Standards derived this way arrive pre-validated, extracted from working integrations rather than negotiated in committee; standards produced the other way arrive as compliance burdens and get implemented with workarounds. What this requires upfront is not detailed specification but shared guiding principles: outcome-driven scope, learn through doing, protected space, and integrated accountability across the programs a slice touches. The principles Minnesota published in their Horizon 3 strategy provide a starting frame CMS is welcome to adapt.