The coast of Tanzania is characterised by a wide diversity of biotopes and species, typical of the tropical Indo- west Pacific oceans, and the peoples living there utilise a variety of its natural resources. Because of the extent of the diversity and variety, several different examples are used by this study to elucidate the complexity of issues and multiplicity of management responses related to use of coastal and marine resources. It emerges that coastal management requires an integrated cross-sectoral approach to address the wide array of interrelated issues involved. The study describes the status of selected resources from the principal biotopes (coral reefs, mangroves, sea grass beds and beaches) as well as fish stocks, and it examines various forms of their utilisation. Some special cases of endangered species are also examined. The study attempts to analyse questions of sustainable use in relation to ecosystem dynamics, socio-economic processes, institutions and policies. The characteristics for what we consider as approaching a state of sustainable use are proposed, and the requirements considered necessary for ensuring sustainability are outlined. Past experience and the current status of coastal and marine resource uses are summarised through the examples chosen in order to explain the main constraints to the attainment of sustainability. Crosscutting issues related to the breakdown of traditional management systems for common property resources in the face of increasing commercialisation, privatisation, and external interventions appear to pose general problems. The general experiences of community projects, legislation, and mitigation measures are assessed from the examples we have chosen. We present an array of general lessons learned and key factors affecting sustainable use of coastal and marine resources. Amongst these we emphasise: • Dialogue and linkage between traditional and scientific knowledge systems. • Mechanisms for interaction between scientists, managers and decision-makers. • Continued human and technical capacity building of research institutions. • Essentiality of addressing land and sea tenure and common property rights. • Genuine involvement and empowerment of local communities and civil society including community- based organisations (CBOs), and local non-governmental organisations (NGOs). • Credible and equitable arrangements for benefit-sharing with communities. • Open availability of information for overall transparency and accountability. • Integration of socio-economic opportunities into conservation programmes. • Recognition of and respect for local and traditional institutions. • Openness in collaboration between traditional and government institutions. • Strengthening of relevant institutions providing entry to decision-making. • Management agreements between institutions for cross-sectoral co-ordination. • Long-term and broad-based visions in policy thinking. • Democratic process of public involvement in policy-making and implementation.