Background: Burden is well documented among carers of stroke survivors, yet current evidence is insufficient for determining the best strategies for reducing negative outcomes. The Medical Research Council (MRC) framework advocates using theories in intervention development, but lacks guidance on how this can be achieved. Interventions targeting carers of stroke survivors often lack theory or provide inadequate descriptions of the active ingredients determining their effects. This research aimed to develop a proposed theory- and evidence-based intervention to reduce burden in carers of stroke survivors. Methods: In conjunction with stakeholder involvement, Intervention Mapping stages one to four guided intervention development: needs assessment; identifying outcomes and objectives; selecting theoretical methods and practical applications; and creating a programme plan. The needs assessment included three components: A systematic review of systematic reviews established the factors that influence burden in carers of stroke survivors and other longer-term conditions; a thematic synthesis of qualitative studies and a qualitative interview study established carers’ needs, how and whether they change over time, and the barriers and facilitators to addressing needs. Findings influenced subsequent stages of intervention development. Results: Stakeholders prioritised the need for carers to feel prepared before and during the transition from hospital to home as key to reducing burden. The proposed intervention comprises multiple components based on theoretical methods and practical applications to target relevant determinants. This includes: a training package for information and support providers working with carers; an additional training session for other staff; and elements to support carers to feel prepared. Conclusions: Using Intervention Mapping addressed some of the limitations of previous interventions and fulfilled MRC recommendations by providing a structured framework for systematically incorporating evidence, theories, and stakeholder input throughout intervention development. Further research is required to produce and refine the proposed intervention components before evaluating their effectiveness.