In the absence of Community rules relating to soil contamination and protection, the Irish authorities have neglected to legislate for this issue. While a few common law tortious grounds of action and certain statutory regimes may be applicable to particular cases of soil contamination, their application is arbitrary and piecemeal, depending, for example, on the type of operation originally causing the contamination, on the extent of understanding of the problem at that time, on the nature of its related adverse effects, or on plans for the future use or development of the contaminated site. One particular lacuna in the coverage of the relevant Irish law relates to the problem of historical soil contamination, for which the Irish authorities have felt unable to legislate on account of a constitutional prohibition on retrospective liability. This paper seeks to set out the possible application of existing Irish rules to the problem of historical soil contamination and to highlight the shortcomings inherent therein. It also outlines the non-legislative solutions employed by Irish lawyers in the face of such legal uncertainty. It then goes on to examine the likely impacts of recent key developments, including the 2004 decision of the European Court of Justice in the Van de Walle case and the entry into force of the 2004 Environmental Liability Directive.