PT - JOURNAL ARTICLE AU - Martin Bricknell AU - T Rowland TI - Delivering effective Defence Engagement (Health): lessons from Operation TRENTON (South Sudan) AID - 10.1136/military-2022-002319 DP - 2023 Mar 10 TA - BMJ Military Health PG - e002319 4099 - http://militaryhealth.bmj.com/content/early/2023/03/09/military-2022-002319.short 4100 - http://militaryhealth.bmj.com/content/early/2023/03/09/military-2022-002319.full AB - This paper describes the Defence Engagement (Health) (DE(H)) component of the medical mission within the UK deployment to South Sudan under Op TRENTON, the UK troop contribution to the United Nations Mission in South Sudan (UNMISS). The DE(H) activities provided advice and mentoring to the Vietnamese military medical services to support the predeployment preparation and training of their medical contingent that would undertake a relief in place of the UK personnel providing a Level 2 hospital in Bentiu, South Sudan. The paper describes these UK DE(H) activities at the strategic, operational and tactical levels to show the integration across these levels from January 2017 until the handover of command in South Sudan on 26 October 2018. The UK worked alongside personnel from the US and Australian military medical services to deliver a Field Training Exercise and other capability-building events for personnel from the Vietnamese 175 Military Hospital. The paper shows how a DE(H) programme can have strategic effects by bringing another nation into a United Nations mission, increasing UK diplomatic activity with a partner country, and by ensuring continuity of medical cover to a key UNMISS location after the withdrawal of the UK medical contingent. This paper forms part of a special issue of BMJ Military Health dedicated to DE(H).