It's hard for us to imagine life without the humble loo. It's a basic necessity; a UN-recognised human right. However, for an overwhelming two thirds of the population in South Asia, a loo is a luxury that's out of reach.
This is more than just an inconvenience; it's a crisis that poses a serious risk on the welfare of one billion people, and it requires urgent action.
Yet sanitation remains an acutely neglected issue, despite the vital role it plays in overcoming poverty and inequality. There have been plenty of high-level political commitments, but the overall progress of sanitation, particularly in reaching poor and vulnerable communities, is unsatisfactory.
This week, in support of a vision of a world with sanitation and water for all, we travelled to Nepal to add our voice to the launch of a campaign that is uniting organisations and communities across South Asia in a call for governments to keep their promises to improve access to sanitation.
The campaign will place pressure on governments to produce separate budget lines for sanitation and increase financing to the sector, as well as determine recommendations on post-2015 development targets for sanitation.
While there, we saw first-hand the problems faced by people with no adequate sanitation, and how a simple latrine can really transform lives, impacting on health, safety, dignity and education.
In Thecho village outside Kathmandu, we met women who were part of a Women's co-operative that was set up to oversee the construction and maintenance of eco-friendly household latrines, vastly improving the quality of life in the community. Before they had latrines, they had no choice but to defecate in the open. The women said this put them at risk of harassment and even attack.
The unsanitary environment also led to health concerns. Diarrhoea caused by poor sanitation and dirty water is the second leading disease cause of under-five deaths in South Asia, and is also linked to pneumonia and under-nutrition. On top of this, sanitation has a significant impact on dignity, education, and livelihoods.
South Asian governments have a responsibility to ensure the right to water and sanitation is realised in their countries. However, with 300,000 children dying from diarrhoea every year in the region, this is also an issue the UK cannot ignore.
We are joining international charity WaterAid in its call on the UK Government to lead the world in prioritising water and sanitation.
Today, World Water Day, WaterAid released a report entitled Everyone, everywhere, showing that universal access to water and sanitation is within reach and, with the right political will and investment, could be achieved by 2030. Achieving this goal could save 2.5 million lives and yield £150billion a year for the global economy.
Next week, international development secretary Justine Greening will attend the fourth and final meeting of the UN High Level Panel on the post-2015 development framework.
At this meeting, the UK government must ensure the importance of water and sanitation is included in the vision that will guide international development efforts beyond the Millennium Development Goals.
Water, sanitation and hygiene are the beginning to better lives, the foundations for eradicating poverty; we must act now.
Find out more at www.wateraid.org/wwd