Release 1.12.1 of the BaRS Implementation Guide includes updates and clarifications to guidance across the standard. The assurance guidance has been revised to remove the fixed “two to four weeks” timeframe. The revised guidance explains that assurance timescales depend on supplier readiness, the completeness and quality of the submission, requests for further information, required resubmissions and the resolution of issues identified during assurance. Application 5 medication and allergy requirements have been clarified. References to “novel” medication and allergies have been replaced with wording that identifies medication administered or prescribed, and new allergies established, during the latest assessment. The MedicationStatement guidance now makes clear that the resource is used to carry new medication prescribed during the encounter and SHOULD NOT be used to carry medication history obtained from external sources. The Core and Application change logs have been improved to distinguish Change Type from supplier Impact. This separates classifications such as Addition and Correction from information explaining what suppliers need to do as a result of a change. Also included in this release are a correction to the Sentinel Element guidance for the Get Referral HTTP 503 test, corrections to external links, an update to the NHS England logo asset used by the Implementation Guide, and other minor bug fixes and corrections throughout the guide.