The expansion of open educational resources (OER) in documents and practice at various levels is related to, among other things, the options these resources offer for the study, sharing, and possibly joint creation of information materials. This has important implications for the knowledge economy, but also the ways of its production and reproduction in education. The article introduces the concept of OER from a legislative perspective (copyright issues), its role in global commitments to sustainable development and particularly in relation to the teaching/learning methods and approaches in the process of their current transformation; the innovative potential of OER for the multidisciplinary field of environment and sustainable development is highlighted. A brief overview of the types of OER which are available in the Czech Republic for the study of environmental and sustainability fields is provided, and qualitative methods of analysis are used to develop a set of criteria through which the quality of the resource can be easily assessed. Different types of OER are evaluated according to these criteria and the overall character of the information environment available to university students is discussed. This brief overview is concluded by underlining significant opportunities of OER particularly in the environment and sustainability oriented disciplines owing to the multidisciplinary nature of these fields. These opportunities, however, are not fully exploited especially because the quality of these resources available on the internet is difficult to assess. Another issue is also the possibility that students themselves are not skilled in distinguishing the quality of resources, and perhaps the reluctance of university teachers to encourage and support students in applying consistent ethical standards in their use of materials in their studies.