Interventions to support and skill paid home carers and managers could potentially improve health and well-being of older home care clients. This is the first systematic review of interventions to improve how home carers and home care agencies deliver care to older people, with regard to clients' health and well-being and paid carers' well-being, job satisfaction, and retention. We reviewed 10/731 papers found in the electronic search (to January 2016) fitting predetermined criteria, assessed quality using a checklist, and synthesized data using quantitative and qualitative techniques. Ten papers described eight interventions. The six quantitative evaluations used diverse outcomes that precluded meta-analysis. In the only quantitative study (a cluster Randomized Controlled Trial), rated higher quality, setting meaningful goals, carer training, and supervision improved client health-related quality of life. The interventions that improved client outcomes comprised training with additional implementation, such as regular supervision and promoted care focused around clients' needs and goals. In our qualitative synthesis of four studies, intervention elements carers valued were greater flexibility to work to a needs-based rather than a task-based model, learning more about clients, and improved communication with management and other workers. There is a dearth of evidence regarding effective strategies to improve how home care is delivered to older clients, particularly those with dementia. More research in this sector including feasibility testing of the first home care intervention trials to include health and life quality outcomes for clients with more severe dementia is now needed.