G8 members have committed to developing a cure or treatment for dementia by 2025 at a summit on the subject in London.
Health ministers said G8 countries would increase funding for research to meet that goal. Earlier Britain said it aimed to double its annual research funding to £132m by 2025.
The global number of people with dementia is expected to treble to 135 million by 2050.
The G8 said it would an international research action plan would be developed to target the gaps in research and ways to address them.
It also called on the World Health Organization to identify dementia as an increasing threat to global health and to help countries adapt to the timebomb.
"We recognise the need to strengthen efforts to stimulate and harness innovation and to catalyse investment at the global level," a statement said.
Dementia is incurable and ultimately leaves people needing full-time care as brain function wastes away.
The BBC reports there is growing concern that some countries will simply not cope with the growing burden of dementia, which cost the world £370 billion in 2010, according to the World Health Organization.