12.19. During the past several decades, the formulation, implementation, monitoring and evaluation of population policies, programmes and activities have benefited from the findings of social and economic research highlighting how population change results from and impacts on complex interactions of social, economic and environmental factors. Nevertheless, some aspects of these interactions are still poorly understood and knowledge is lacking, especially with regard to developing countries, in areas relevant to a range of population and development policies, particularly concerning indigenous practices. Social and economic research is clearly needed to enable programmes to take into account the views of their intended beneficiaries, especially women, the young and other less empowered groups, and to respond to the specific needs of those groups and of communities. Research regarding the interrelations between global or regional economic factors and national demographic processes is required. Improved quality of services can be achieved only where quality has been defined by both users and providers of services and where women are actively involved in decision-making and service delivery.