Aim: Identifying the intervention mechanisms is important in understanding how and why they are effective. Using the Behaviour Change Technique (BCT) taxonomy V1, this study examined which home care worker intervention components drive behaviour change and improve outcomes for people living with dementia and family carers. Method: A systematic review was conducted of randomised controlled trials. Home care workers included both care professionals with and without professional qualifications. We searched from inception to September 2024: MEDLINE, CINAHL, PsycINFO, EMBASE and EMCARE databases. We evaluated risk of bias and intervention effectiveness, and used BCT taxonomy to quantify the frequency of BCTs targeted at change for home care workers and care recipients. Results: 29 articles met eligibility including six articles from the USA, four respectively from Hong Kong, UK, and Australia; two respectively from Canada, Taiwan and Finland; and one each from Japan, Norway, China and one multinational paper. 18 of 29 studies reported interventions on or with home care workers who had professional qualifications, e.g. nursing. The main target behaviour change areas were knowledge and competence for home care workers and family carers (n=10), reducing carer burden (n=9), and managing behavioural symptoms (n=8). Discussion/implications: Findings highlight that targeting home care workers’ knowledge and competence can have meaningful impact on outcomes for people living with dementia and their family carers. These findings emphasise workforce capability as a key mechanism for improving community dementia care, while recognising family carers as integral contributors. Future research needs to move beyond reporting only on effectiveness to examine the mechanisms through which interventions produce change.