The Standard

The HL7® FHIR® at Scale Taskforce (FAST) and the CARIN Alliance are joining forces to deliver the next generation of interoperable digital identity for U.S. healthcare. Together, we are aligning FAST Identity STU 3 with the CARIN Digital Trust Framework so that patients, providers, payers, and the networks that connect them can rely on a single, consistent foundation of trust as the CMS Aligned Networks ecosystem comes online.

This is more than a technical collaboration. It is a strategic commitment by two of the most active organizations in U.S. health data exchange to ensure the trust layer beneath nationwide interoperability is open, interoperable, and ready for scale.

Why This Partnership, Why Now

The CMS Health Technology Ecosystem and the Aligned Networks Pledge have raised the bar for what “connected” means in healthcare in the United States. Twenty-one networks have already committed to meeting the CMS Interoperability Framework criteria — and every one of them needs a way to answer a deceptively simple question every time data moves: who is on the other end of this transaction, and can we trust them?

FAST has spent years building the scalable, FHIR-based infrastructure that answers that question — identity matching, certificate-based trust, federated directories, and computable consent. The CARIN Alliance has spent equal effort building the policy fabric that makes credentials portable across organizations. The CARIN Digital Identity Credential Policy, published in September 2025, defines an open trust framework that lets credentials issued by one Credential Service Provider be recognized and accepted by another — grounded in NIST SP 800-63 identity assurance levels, NIST 800-53 controls, and the RFC 3647 policy structure used by mature certificate ecosystems.

The opportunity before us is to wire these two efforts together — not in parallel, but as a single, coherent stack that the industry can adopt.

What We Are Building Together: FAST Identity STU 3

FAST Identity STU 2 was published in December 2025, delivering implementer-validated guidance for identity matching across organizational boundaries using FHIR Patient, Person, and RelatedPerson profiles, the FHIR $match operation, and the HL7 Person Identifier as a persistent, interoperable identifier for longitudinal correlation.

FAST Identity STU 3 picks up where STU 2 left off. Working hand in hand with the CARIN Alliance, we are extending the implementation guide so that:

• FHIR-based identity workflows are bound to externally accredited identity assurance, so that an IAL2 or IAL3 credential issued can be recognized and honored anywhere in the FAST ecosystem, without each relying party performing its own independent evaluation.
• Federated workflows align with Tiered OAuth, OpenID Federation, and identity broker patterns — the same building blocks CARIN identifies as foundational to cross-framework reciprocity.
• Identity resolution scales across consumers, providers, payers, and applications, so that participants can prove who they are once and be trusted everywhere a FAST-conformant network reaches.

The result is a clear, implementable path from verified human or organization all the way to FHIR data exchanged with the right party, under the right consent, on the right network.

On behalf of the HL7 US Realm Steering Committee (USRSC), we are pleased to share an update on last year's priorities and highlight our focus for 2022.

2021 Highlights

Visibility was a key theme of our work in 2021 and included supporting pilot work on a standards dashboard, tracking accelerator activity and promoting key ballots.

Before we dive into 2022, we want to highlight a few key points for all US Realm (USR) members.

• SMART v2: published new guidance on granular controls
• Bulk Data v2: published with numerous new features 
• Errata release of Consolidated CDA (C-CDA): companion guide to support January 2022 ballot  
• C-CDA Companion Guide: January 2022 ballot to add USCDI v2 guidance
• US FHIR Core - January 2022 ballot: to add USCDI v2 guidance
• Hosted reviews on HL7 Standards Dashboard Prototype
• C-CDA Web Publishing Trial Draft using FHIR Structure Definition
• Facilitated US@ project with ONC team

Sessions at HIMSS21 Offer Glimpses into Progress, Potential New Uses for the Standard

After a hiatus of nearly 18 months, a slimmed-down, COVID-sensitive HIMSS 2021 Conference still managed to provide extensive insights into several major trends within the healthcare IT industry.

Along the dual tracks of federal regulations forbidding information blocking and the need for improved data exchange to facilitate, there were many discussions about the capabilities of HL7® Fast Healthcare Interoperability Resources (FHIR®) to support the industry.

The HL7 FHIR community had opportunities at the conference’s Interoperability Showcase to update the industry on dramatic progress by its accelerator groups to advance the use of FHIR in areas where data exchange is essential.

The Centers for Medicare & Medicaid Services (CMS) released the much-awaited Interoperability & Patient Access Rule in early March this year. This rule establishes policies that aim to break down barriers in the health system across the US for better patient engagement. Government bodies are taking significant efforts for governments-sponsored health plans to adopt interoperability to make healthcare system efficient. Multiple initiatives by the Department of Health and Human Services (HHS) and its CMS and Office of the National Coordinator for Health Information Technology (ONC) aim to improve care-coordination and member experience. CMS had proposed the Interoperability & Patient Access Rule to support regulations of the MyHealthEData initiative, with implementation timelines to drive programs such as BlueButton, BlueButton 2.0 and Data at the Point of Care.

In the times of pandemic, healthcare organizations have realized the importance of having access to data for better care coordination and efficient care delivery. With seamless data access, organizations can:

• Share health data of beneficiaries with different care teams
• Identify high-risk population and implement preventive actions to control risk
• Leverage tele-health with access to patient historical health data
• Take timely decisions on emergency treatments based on patient medication history

The Virtual FHIR Patient Access API Implementation Event Scheduled for  August 17-19

The start of the New Year will see healthcare organizations facing new requirements for using application programming interfaces (API) to facilitate the sharing of healthcare information.

That’s made clear by the recent release of final rules by the Centers for Medicare & Medicaid Services (CMS) and the Office of the National Coordinator for Health Information Technology (ONC), which will be the first step in enabling data access.

To help support healthcare organizations in this shift, HL7 is holding the virtual FHIR Patient Access API Implementation event next week. With the impending final rule and the looming implementation deadline, this event will be narrowly focused on the requirements for patient access APIs by payers.

The goals for this Implementation-a-thon and associated educational events are to inform the broader community of the work HL7 FHIR Accelerators have done to lay the groundwork for meeting the final rules; and to help participants prepare for the September HL7 FHIR Connectathon and 34^th Annual Plenary & Working Group Meeting.

Education and specific planning in API implementation in a FHIR environment will be important for the industry, as these recently released federal rules require that consumers be able to access their medical information through third-party apps, and that will place pressure on healthcare organizations to develop APIs to enable this access. The HL7 Da Vinci Project continues to develop use cases that will facilitate this patient access to information.