One of the objectives of this paper is to precisely define the phenomenon of pro-environmentally motivated crimes, as well as to provide its objectified presentation and analysis. Instead of the term eco-terrorism, which dominated the literature so far, the author offers the term proenvironmental crime, explaining that it far better suits the diverse nature of the specter of illegal environmental activities. As narrower categories, categories of pro-environmental vandalism, pro-environmental diversion, i.e. sabotage and pro-environmental terrorisms (in its narrower sense) are formulated, together with suggestions for further organisation and specialisation of research within those. The author introduces the additional term of anti-environmental crime to define illegal activities with consequences in endangering and disturbing the balance within the ecosystem. Argumentation is provided in favor of re-evaluation of the level of danger to the society, which is the result of environmental activism, particularly bearing in mind the declared pacifist approach of the majority of environmental associations, whose programs explicitly condemn assaults to physical integrity, opposed to numerous militarist, classic terrorist organisations, both national and international. At the same time, the readers' attention is drawn to shortcomings of unification of pro-environmental crime, without taking into account the differences between particular illegal acts, as well as the character and value of endangered goods. Speaking of positive law aspects, the author identifies an unambiguous necessity to equally treat each environmental activist tendency which confronts the legal norms in force, as well as to prosecute the persons responsible, in the interest of the rule of law and legal certainty. On the other hand, the author supports the idea of reassessment and further improvement of relevant legislation, particularly having in mind the complex nature and immense importance of environmental issues in the context of the future of our global community. The essential importance of preservation of the environment provokes additional examination of possibilities for future relations between state authorities and scientists and experts, on one side, and environmental activists, on the other, while the author concludes that every improvement in understanding the nature and characteristics of current environmental issues would have multiple benefits. Systematic research and proper understanding of disturbances in the ecosystem and dangers towards it, including monitoring and analysis of tendencies in pro-environmental crime, seam as steps forward in the struggle to preserve the balance in global environment, while it would at the same time reduce the reasons for further use of eco-criminal techniques, which, finally, creates an additional perspective towards legally acceptable methods of environmental activism.