Background. Cognitive functions are important for daily life at any age. One purpose ofSmart Ageingis to investigate how to improve cognitive functions. This systematic review evaluates beneficial effects of the intervention on cognitive functions.Method. We conducted a systematic review of intervention studies of improvements of cognitive functions published or in press before December 2013. Because of the heterogeneity of the intervention programs, a systematic and critical review of the interventions and outcomes was conducted instead of a meta-analysis.Results. We identified nine completed and published studies, which were divided into four categories: cognitive training using video game, cognitive training using PC, cognitive training using paper and pencil, and exercise training. Review results showed that various intervention programs can improve cognitive functions such as executive functions, working memory, episodic memory, processing speed, and general cognitive ability/IQ.Conclusions. The systematic review demonstrated that some intervention programs can be effective for improving various aspects of cognitive functioning at any age. Some limitations to this review include its small sample size and heterogeneity of programs and cognitive function measures, in addition to unresolved issues such as transfer of everyday skills and effectiveness for nonhealthy people.