Throughout the history of the North Sea as an oil province, the regulation of health and safety at work has proved both difficult and contentious. Successive regulatory approaches have been introduced ranging from an initial formal system in which there was no substantive state intervention, through detailed prescription to the present goal-setting and auditing approach but in each case the law has eventually been accused of being part of the problem rather than the solution. Subjected to the scrutiny of economic and capture theory analyses, the industry and its regulators present an easy target and the economic and power relations revealed tend to favour the lough enforcement of detailed prescriptive regulation. The Piper Alpha disaster in 1988, however, seemed to suggest that this was precisely the sort of approach that was inadequate in the context of an industry as complex as offshore oil. The new regime introduced in the aftermath of that disaster which was intended to meet these difficulties has, however, recently been characterised as deregulation and has produced calls for the reintroduction of prescription. The danger of a vicious circle here is clear. This thesis employs a different understanding of regulation and its relationship with the regulated area to reveal the ways in which the prescription/deregulation debate and the models of law which underlie it can mask important features of the regulatory landscape. Drawing on the theory of autopoiesis, the notion that the study area is best understood as being composed of operationally closed but cognitively open communicative systems is taken seriously. The ideas of the system-specific construction of reality according to fixed codes and of self-steering according to variable programmes of difference- minimisation are considered along with their implications for regulation. From this understanding, a methodology based on cognitive mapping is developed which allows the processes of the different systems to be presented in such a way as to allow a second-order observation - that is to say, an observation of what it is that each system can and cannot observe. This approach is used to examine in particular the systems of industry management and of engineering throughout the history of the North Sea as an oil province, as well as the world constructions of politics and of the regulators. Significant among the findings which emerge from this approach are the difference-minimising programmes to which industry management and engineering have operated at various periods. Operating to a programme of the minimisation of economic risk by means of rapid production during the 1970s, for example, industry management was unable to observe the technical and occupational (and, paradoxically, ultimately economic) risks this programme produced. Similarly, the technical risk reduction programme of conservative determinism by which engineering steered itself during the same period served to mask a variety of important factors relevant to the integrity of offshore installations which served in turn to increase costs and thus the economic risk of oilfield developments. In the light of this understanding, the regulatory expectations of politics are revealed as hopelessly inadequate and the full extent of the regulators’ difficulties in the context of a prescriptive regime becomes clear. A similar examination of the 1980s, reveals tentative moves in both industry management and in engineering towards more risk-aware programmes followed by their eventual abandonment in favour of drastic programmes of cost-reduction in the aftermath of the 1986 price collapse - the setting for the Piper Alpha disaster. This leads into an assessment of the new approach to the regulation of health and safety offshore which was introduced following that disaster. By revealing the constructivist and self-steering aspects of the communicative systems of which the regulated area is composed, this approach highlights the difficulties facing prescriptive regulation as well as the dangers of any deregulation. This understanding also reveals the reflexive potential of the new regulatory approach, however. That is to say, its ability to harness the risk-aware programmes in the industry and encourage an ongoing confrontation with the assumptions underlying its operations. The importance of such an approach is demonstrated by an examination of possible risks arising out of new industry management programmes of economic risk reduction - programmes which superficially mark a step change from previous determinism. It is suggested that only by understanding the new approach as an example of reflexive law can the possibility of a vicious circle returning ultimately to prescription be avoided. Only in this way can the masking effects of management and engineering models and of standard legal models be avoided.