Environmental policy Sustainable development 157 Environmental aspects 131 Environmental protection 94 Economic aspects 83 International cooperation 60 Environmental economics 57 Government policy 57 Environmental management 51 Climatic changes 49 Economic development 38 Natural resources 35 Environmentalism 33 Environmental law 30 Environmental sciences 27 Pollution 24 Human ecology 21 Case studies 19 Political aspects 19 Social aspects 19 Decision making 18 Citizen participation 17 Environmental impact analysis 16 Conservation of natural resources 15 Energy policy 15 Management 15 Economic policy 14 Environmental conditions 13 Globalization 13 Green movement 13