Shining the spotlight on household investments for water, sanitation and hygiene (WASH): let us talk about HI and the three 'T's

This editorial argues that the use of the three 'T's financing source framework (taxes, tariffs and transfers) leads us to ignore key costs to the customer, especially the poor customer, of accessing an adequate level of the water, sanitation and hygiene (WASH) service. These costs include household investment (HI) for self-supply (commonly excluded from tariffs). We propose an adaptation to the framework, which we call 'HI and the three T's'.