OBJECTIVES: The burden of caregiving is high. In 2009 there were an estimated 65.7 million caregivers in the U.S. (29% of the adult population) and these numbers are expected to swell in the coming years with the ageing population. Caregiving impacts on the health, wellbeing and work productivity of the caregiver, therefore research aimed at assessing and reducing the burden of caregiving is warranted. The objective of this study was to assess the status of current clinical research into the burden of caregiving. METHODS: Clinicaltrials.gov was searched for trials where caregiver burden (CB) was reportedly measured. Information on the care-recipient condition (CRC), the primary focus of the study, and the type of intervention being considered, was extracted from the included trials. RESULTS: 80 trials were identified that measured a reported outcome of CB. The most common CRC was Alzheimer’s disease and related disorders (34 studies); followed by cancer (14), frail and elderly (8), mental health (7), Parkinson’s disease (7), brain and spinal cord injury (5) and ‘other’ (5). A range of questionnaire-based instruments were reportedly used across studies to elucidate the physical, emotional (psychological), social and financial impacts of caregiving.The role or burden of the caregiver was a key focus in 55% of the studies; trials involving care of cancer patients had the highest proportion of caregiver-focused studies (12/14, 86%). Behavioural and drug interventions were the most frequently investigated intervention type (38% and 25% of trials, respectively), although no studies investigating a ‘drug’ intervention evaluated the effect on caregivers as a primary outcome. CONCLUSIONS: Current clinical research into the burden of informal caregiving is concentrated in age-related CRCs. Research interventions aimed at relieving CB are mostly behavioural in nature. The growing number of caregivers means that research into effective methods of reducing CB will be of ever increasing importance.