the technical cooperation ends. Institutional sustainability can also be linked to the concept of social sustainability, which asks how the interventions can be sustained by social structures and institutions; Economic and financial sustainability. Can the results of technical cooperation continue to yield an economic benefit after the technical cooperation is withdrawn? For example, the benefits from the introduction of new crops may not be sustained if the constraints to marketing the crops are not resolved. Similarly, economic, as distinct from financial, sustainability may be at risk if the end users continue to depend on heavily subsidized activities and inputs. Ecological sustainability. Are the benefits to be generated by the technical cooperation likely to lead to a deterioration in the physical environment, thus indirectly contributing to a fall in production, or well-being of the groups targeted and their society? Some ecologists have emphasised a fourth type of sustainability: Energetic sustainability. This type of sustainability is often concerned with the production of energy and mineral resources. Some researchers have pointed to trends they say document the limits of production. See Hubbert peak for example. "Development sustainability" approaches Sustainability is relevant to international development projects. One definition of development sustainability is "the continuation of benefits after major assistance from the donor has been completed" (Australian Agency for International Development 2000). Ensuring that development projects are sustainable can reduce the likelihood of them collapsing after they have just finished; it also reduces the financial cost of development projects and the subsequent social problems, such as dependence of the stakeholders on external donors and their resources. All development assistance, apart from temporary emergency and humanitarian relief efforts, should be designed and implemented with the aim of achieving sustainable benefits. There are ten key factors that influence development sustainability. Participation and ownership. Get the stakeholders (men and women) to genuinely participate in design and implementation. Build on their initiatives and demands. Get them to monitor the project and periodically evaluate it for results. Capacity building and training. Training stakeholders to take over should begin from the start of any project and continue throughout. The right approach should both motivate and transfer skills to people. Government policies. Development projects should be aligned with local government policies. Financial. In some countries and sectors, financial sustainability is difficult in the medium term. Training in local fundraising is a possibility, as is identifying links with the private sector, charging for