This thesis is about the distrubution of responsibilities in the environmental law enforcement procedure, between the state and the individual environmental actor. The state and its public authorities have a fundamental environmental responsibility. This responsibility is nevertheless shared with the actors. Actor responsibilities include taking sufficient precautionary measures,and controling the own activities. This also covers responsibilities for knowledge and investigation, which are in focus in the thesis analysis. Such responsibilities are enforced by administrative authorities. Enforcement, however, also entails exercise of public power against the individual, and thus warrants proper procedure and safeguards of legal certainty. Such procedural responsibilities include ensuring decision making materials to support their exercise of authority. It also means that the authority has formulate clearly to the actor what their legal duties are, and what they need to do to avoid further enforcement. These administrative dutiesmay entail the authority taking over the actor's information responsibilities under environmental law. Enforcement of actor responsibilities thus becomes inconsistent, or even contraproductive.

This thesis comprises analysis of the meeting of environmental and administrative law in the enforcement situation. The analysis is focused on balancing effective implementation and enforcement of policy aims, and the safeguards of the individual's rights and freedoms. The aims is to find ways to coordingate instead of prioritising these objectives. The research is based on a comparative study and analysis of the enforcement systems of Sweden, the United Kingdom (England and Wales), and the Netherlands. The importance of distinguising between the different purposes and aims of the responsibilities is argued. Actor responsibilitiesfor precaution and information should be recognised also in the enforcement procedure. A communicative enforcement procedure, and more purposive assessment of the properdistribution of responsibilities in the individual case may provide both effective enforcementand legal certainty.