Sustainable development economically successful, socially responsible and at the top, environmentally sound. Aims for stable or mildly fluctuating levels in population and consumption energy and materials. Birth rates equal death rates, and saving/investment equals depreciation. Using goods and services for our basic needs. Minimizes use of resources, preserve for future generation. Many renewable resources being used in a nonrenewable way timber, water, etc. First defined by garret hardin in 1968. Commons: available to everyone but no single individual has responsibility. Tragedy: short term individual welfare trumps long term environment. Global scale: dependent on two things: birth rate (b, death rate (d) R = b d (in a particular time period) Growth rate = (birth rate + immigration rate) (death rate + emigration rate) Large organisms small biotic potentials (whale) When this occurs we say it has reached its carrying capacity. Carrying capacity largest population that can be sustained indefinitely.