As part of BBC's Water Debate we asked experts from all around the world what is the single most important thing we could do to make a difference to the situation.
Select a link below to hear what each expert had to say:
If you would like to send us your comments on any of the issues raised get in touch using the form on the right.
Mahmoud Abu-Zeid is president of the World Water Council.
He is also Minister of Irrigation and Water Resources for Egypt.
The missions of the World Water Council are to promote awareness and build political commitment on critical water issues.
Dr Ghosh is Executive Director of Water Supply and Sanitation Collaborative Council.
The council was set up in 1989, as a product of the International Decade for Water Supply and Sanitation.
It puts water professionals in touch with each other to share knowledge, and organises regular international meetings to discuss the progress of getting safe water and sanitation to poor communities.
Ravi Narayanan works for the British charity WaterAid.
Wateraid works in 15 African and Asian countries, helping communities gain access to water and sanitation.
They also work to influence government policies on water.
Margaret is the chairperson of the Global Water Partnership.
Her organisation aims to create a partnership between all the different agencies involved in managing water resources.