Cost benefit analysis approach to global claims LordWayne GrayT.E. 2011 Purpose – The purpose of this paper is to examine relevant case law governing the failure and/or success of global or rolled-up claims, where it is said to be impractical or impossible to demonstrate the links between certain causes of action and the monetary value to be attached to each. The paper proposes a theoretical framework to improve a claimant’s prospects of success in advancing a global claim, not only in circumstances where it may be impractical or impossible to provide a breakdown but also where a cost benefit analysis concludes it is reasonable to do so. Design/methodology/approach – The paper uses traditional doctrinal legal methodology to evaluate judicial statements on the merits of global claims from a number of jurisdictions. The paper also draws on key authorities from the realms of health and safety and professional negligence. Findings – The cases demonstrate attempts by the court to recognise the problems faced by claimants at the end of a construction contract where their total costs exceed the agreed contract price. The comparative success or failure of a global claim depends on the judicial approach to a number of factors including: impossibility, impracticability, conduct of the claimant and defendant, balance between excessive particularity and basic information, the keeping of records, the costs of claim preparation and apportionment. There remains a significant risk of failure of a global claim but the risk can be reduced significantly provided the claimant conducts a defensible cost benefit analysis of the approach taken. Practical implications – A global claim can be used more often provided the rationale behind its presentation forms a logical basis. The cost of litigating complex construction contracts can be reduced significantly if global claims can become the norm rather than the exception, provided the claimant conducts a cost benefit analysis and the court concludes the analysis is reasonable and defensible. Originality/value – Traditional legal theory relies upon the proposition that the claimant must prove that to which he believes he is entitled to such an extent that the defendant’s right to know the case it has to meet is satisfied. This paper adds value to the theory by proposing a radical strategy whereby a reasonable claimant can assist the court in finding a factual and logical basis for awarding the whole of a global claim and, where appropriate, by deduction in addition to the principle of apportionment, less than the whole.