The principle that contracts are made to be kept, articulated in the old maxim-pacta suntrnservanda- perhaps comprises the bedrock of all contract law systems. The principle, however,rnhas never been regarded absolute throughout its history: almost all legal systems traditionallyrnrecognised limitations on its application, particularly where unforeseen supervening eventsrnmake performance of contracts absolutely and objectively impossible. However, suchrnuniform position is lacking among legal systems when it comes to how the law shouldrnrespond to the cases in which the supervening circumstances merely render performance ofrncontracts extremely burdensome or the counter-performance to be received virtuall yrnworthless to one of the parties. These latter cases formed the main focus of this research: andrnthe generic expressions 'the problem of change of circumstances' and 'the doctrine of changernof circumstances', have been respectively employed to refer to the questions involved thereinrnand the specific legal devices applied to address them.rnThe doctrine of change of circumstances found its original expression in another old maximrnof contracts law- the ribus sic stantibus - which embraced the core idea that contracts stay thernsame only so far as the states of affairs present upon their conclusions remain constant. In itsrnearly application, the doctrine was viewed as an implied condition attached to all contractualrnpromises. Due to this reason, its application was never perceived to contradict with the otherrnparamount principle of contracts law- pacta sunt servanda. Thus it enjoyed wide-spread acceptance among legal systems, before the oppositions based on the 19 th century classicalrntheories of contracts later brought its demise. Application of the doctrine was deplored by thernclassical views to cause erosions to the core principle of binding force of contracts, andrnthereby threaten freedom of contracts and security of transactions. At least for some period,rnthis led to its disappearance from the legal scene altogether. But it once again started to re-rnemerge in many jurisdictions, particularly due to the post-WWI and WWII huge economicrndislUptions caused in many parts of the world. This marked the final comeback of therndoctrine and its continued acceptance both in the theories and applicable IUles of the modernrncontracts law.rnThis study was thus commenced with the basic objective of identifying the justificationsrnbehind this modern comeback of the doctrine and how it may be related to ensuringrnX