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Interoperability Toolkit: Guidance for developers

A collection of software developer resources.


ITK Payloads – HL7v3 and Clinical Document Architecture

The NHS Interoperability Toolkit (ITK) provides specifications for electronic messaging between systems, supported by an accreditation for suppliers who build solutions that adhere to these specifications. This page explains the two main areas; transport and payloads.


NHS Interoperability Framework

The Interoperability Toolkit (ITK) is a set of national standards, frameworks and implementation guides to support interoperability within local organisations and across local health communities. The ITK is not a piece of software.


ITK3 Test Harness

NHS Digital has developed a set of generic FHIR messaging components to allow a standard approach to FHIR MessageHeaders and responses across NHS message and document flows in England. These components, along with NHS Digital payload specifications, are part of the ITK3 solution.


Transfer of Care - FHIR API

The Transfer Of Care (TOC) specifications contain new and previous versions of Acute Inpatient Discharge, Emergency Care Discharge, Mental Health Discharge, Outpatient Clinic Letter.