Conclusion

The core idea underlying the assumption of responsibility appears to be that the defendant has engaged in some conduct in relation to the claimant, or a class of persons including the claimant, which changes the legal relationship between the claimant and the defendant.

It is overwhelmingly clear from the cases that we are not concerned here with voluntarily assumed obligations. Nor can we say that the defendants in all of the relevant cases have chosen to enter into a relationship with the claimant in which care can reasonably be expected. What characterises the assumption of respon­sibility cases is simply that the defendant has accepted a role, or embarked on a task, in which the claimant is so closely and directly affected by the defendant's acts and omissions that the defendant ought to have the claimant in contempla­tion when considering whether and how to act. The assumption of responsibility is not, therefore, a distinctive category of obligation, but a loosely defined subset of proximity. What is crucial is not the undertaking made by the defendant, but (a) the nature of the relationship that is entered into, (b) what may reasonably be expected of the defendant in that relationship and, (c) most importantly, the potential effect of the defendant's conduct on the claimant.

It has been said that Lord Atkin was wrong to claim in Donoghue v Stevenson that there must be and is a general conception of duty, because Hedley Byrne revealed or reminded us that there is not one general conception of duty, but at least two: the neighbour principle and the assumption of responsibility.^[465] The analysis here suggests that in fact Lord Atkin was right. The assumption of responsibility is not a distinctive category of obligation, but simply a particular manifestation of the neighbour principle.