Background: A growing number of studies of informal carers of older people reveal positive results concerning support via Information and Communication Technologies (ICT). Systematic examination of factors that have a potential impact on carer outcomes are needed to inform future research.; Objective: To explore studies concerning ICT support of adult carers of older people and to identify study characteristics that have a potential impact on carer outcomes.; Methods: This integrative review includes 123 studies published since 2005. Fundamental questions for designing sensitive support interventions; 'who, what, and how' were applied to a synthesis of the results.; Results: Identified characteristics from the studies responding to the who question included variables of the carers, such as their relationship with the care recipient or their ethnicity. Characteristics related to the what question related to the types of interventions, and the how question concerned the different services or programs offered, the idiosyncratic needs of the carers, and the types of technologies used.; Conclusion: Results are discussed according to micro, meso and macro levels of analysis. This extensive review can inform future studies and highlight the evidence in the area for decision makers, practitioners and/or NGOs working with innovative forms of support for carers of older people.