For sustainability of all development initiatives Financial, Institutional, Environmental, Technical, and Social sustainability elements (together forming the acronym 'FIETS', or 'bicycle' in Dutch) are crucial. However, and not surprisingly, financial sustainability tops the list, as without the highest possible degree of user contribution for service provision 'sustainability' will always remain a dead letter. WASTE is at the forefront of developing innovative finance mechanisms to ensure that interventions in waste management and sanitation can be sustained by local resources as much as possible. In this view donor funds are only used for activities that cannot reasonably be financed locally. 'Innovative' is the establishment of direct contacts between local financiers with local buyers of products or services, be they households, or small enterprises selling goods and services to poor households. It may be useful, in this respect, to temporarily deposit guarantees (from donor funds, or from Western finance institutions) with local finance institutions. This will make it easier for them to regard the poor as 'bankable proposition', and to serve as -temporary- collateral. Another element of 'innovation' is that subsidies to the poor should preferably result from sustainable local political processes, and not be financed from donor funds. In other words: subsidies should result from a normal relationship between tax-payers and tax-collectors.