This essay seeks to illustrate the role that 'Common law' and 'Case law' has played in the development of UK health and safety statute. The author will seek to explain the origins of Common law, its application and its interrelationship with statute law, in terms of statutory interpretation and the doctrine of judicial precedent. Both positive and negative aspects of such systems will be discussed during the course of the essay. The origins of UK common law date back to the reign of Henry II. Prior to the Norman conquest in 1066, Britain consisted of several kingdoms, of which each held their own customary laws and methods of applying and enforcing justice. Although the Normans were successful in their conquest of England at the battle of Hastings in 1066 resulting in the unification of the country, a common legal system was not achieved fully until 1154 during the reign of Henry II through the existing courts of the time, 'the Kings Bench', 'Court of the Exchequer' and 'the Court of Common pleas'. The unification of the legal system to 'commonly' apply to all of the country's subjects was to be applied uniformly and consistently across the country by a circuit of travelling judges, dispensing justice based on past decisions (precedents) in court known as; In terms of the application of a judicial precedent, a court must consider if the earlier decision is applicable as a 'Binding Precedent', whereby the relevant 'statement of facts' are the same in each case and must be followed by a court of the same or lower standing, or that the earlier decision is applicable as a 'Persuasive Precedent' because, although not all of the criteria of a binding precedent has been met, other factors are contained in the previous decision that maybe influential. In the event of a conflicting point of view on a specific point of law, then the hierarchy of the court system is relied upon; higher courts set legal precedent for lower courts. This was illustrated in the case in the case of Dickins v O2 in 2008, whereby the claimant Ms Dickins had brought a successful claim against the defendant O2 for psychiatric injury due to excessive stress. On appeal, the defendant had argued; Common law and its judicial precedent have the advantage of providing certainty to cases that are the same and also direction to those that are alike. There is also an inherent flexibility within common law that allows for judicial decision to develop with the social expectation of its citizens and general societal change. However, the common law system also has an inherent disadvantage; that judgements on cases are only made following that they have been brought before the court. In the context of health and safety in the UK during the industrial revolution which began at the start of the 18th century, the reactive nature of common law did little to ease the suffering of workers, many of which were children, working in appalling conditions where serious injury and death were commonplace. Statute law, as opposed to common law, is in essence the formulation and enactment legislation by parliament on topics of societal concern that requires legislative control. The term legislation not only covers acts of parliament, but also statutory instruments or delegated legislation. In order to be accepted into statute, an act of parliament begins as a proposed bill (Public, Private or Members) and is required to go through a 'white paper' process of consultation within the houses of parliament and Lords in order to be accepted into statute law. The legislation will only come into force on the day it receives its royal assent or alternatively on the day specified by the act itself. The doctrine of 'parliamentary sovereignty' means that statutes passed by parliament cannot be challenged. Delegated legislation or 'Statutory Instruments' do not go through the potentially lengthy and uncertain consultation process of a 'Bill' and can be made under the authority of its primary legislation (enabling act). Statutory instruments have the advantage of being drafted and implemented quickly in response to issues /incidents that have arisen or occurred that require legislation to apply specific duties in order to protect people or the environment from harm. An example of this followed the Piper alpha disaster in 1988 and the subsequent legislative response. The interrelationship between the development of statutory instruments under health and safety legislation, their enforcement and inspection would set a precedent for the way in which future legislation would be developed. However, the Factories Act 1833 and subsequent legislation up until 1974 was compartmentalised and developed in a piecemeal fashion. The only general duties that existed prior to the enactment of the Health and Safety at Work Act 1974, existed within common law and its judicial precedent (particularly within the 'Tort' of negligence). The volume of case law and statutory legislation concerning health and safety and the resultant established duties placed upon employers, in correlation with the rapidly expanding and diverse number of industries within the UK by 1970, required a consolidation of UK health and safety law and the application of a generalised approach that gave protection to all employees in all modes of employment. With the formation of the Robens committee in 1970 and its published report in 1972, found that; It follows that there has been an obvious synergy between common law and statute in the development of health and safety legislation. In isolation, they have in their own right been less effective, than in their 'coming together' since the development of the Health and Safety at Work Act 1974. Although the UK workplace has dramatically changed since 1974 with a shift from heavy manufacturing to a service based economy, this has posed new challenges for health and safety law. More recently, the emergence of workplace stress has become a significant concern for employers and employees alike. For example, the publication 'Nursing times' stated in 2009; The publication of HSG 218 'Managing the Causes of work related stress' in 2007 does not appear to be sufficiently effective given that between its publication in 2007, up to 2009, statistics show that cases of stress were broadly the same. Could the absence of statute on the subject be having a negative effect? The author believes so, given that the incidence rate of this work related illness is so high and has not been impacted on by the publication of health and safety guidance. However, the synergy between common law precedent and statute lies paradoxically in the heart of this subject as it did prior to the enactment of the Health and Safety at Work Act 1974. Whereby, common law judicial decision and its subsequent precedents (as seen in Dickins v O2) will give guidance for the future development of legislation that must surely follow in order to make sufficient improvements which will effectively protect employees from work related stress.