Nowadays, education for sustainable development starts covering wider and wider spheres of interest and human activity. Out of the three main spheres of interest, such as environmental, economic, and socio-cultural, the first two mentioned here seem to be given more attention than the sphere of socio-cultural activity. In this respect, the aim of the present paper is to redirect the concern of administrators, researchers and educators preoccupied with sustainability to issues such as equal opportunity, tolerance, respect, and especially foreign language education, being component parts of the socio-cultural sphere. Undoubtedly, competence in the socio-linguistic field becomes the decisive element in negotiations and international contacts which require from the language user to be tactful and tolerant. Since sustainability is not a local issue, all sustainability related problems ought to be discussed on the macro scale, which requires an internationally shared means of communication such as language. Although no name of any language appears in the paper, it becomes evident that the attention is directed towards English as an internationally recognized language or, if necessary, any other language which might serve as a means of communication on the macro scale. In the course of discussion, both the needs and limitations appearing in the process of education for sustainable development are presented and supported by opinions and examples. The paper ends in conclusions directly related to real-life situations, and gives implications to be utilized in the educational process directed at sustainable development.