Present article attempts to offer basic, rigourous and grounded information about Environmental Ethics. In its six parts it treats the following issues: The pressing necessity of advancing in the construction of an ethical theory, capable of dealing with moral problems arosen to the mankind by the extent and profoundity of its power over nature. The radical changes operated in our century by technoscience developments, on the traditional conception of the relations man-nature. The ontological dignity of living beings and the real capacity of transformation or reelaboration of possibilities offered by nature, as moral limits for human action over the world. Three foundamentals types of problems for Environmental Ethics: International, Intergenerational, Interspecific. Two great strands in Environmental Ethics thought: anthropocentrism and anti- anthropocentrism, each one with its fragmentations and more or less profound differencies. Finally some bibliographical indications are offered about leading works on the issue.