He was educated at the University of Vermont, USA (BA, 1950, majoring in Sociology) and Harvard (LL.B., 1955) where he studied contracts under the noted theorist Lon L. Fuller.
He served as an infantry Lieutenant in the US Army from 1951 to 1953 and remained in the reserve until 1969, when he was honourably discharged with the rank of Major.
Notable events during his tenure included his gifting of the crofting estate of Barra to the Scottish nation, and his granting of a lease of the medieval Kisimul Castle to Historic Scotland for 1000 years at an annual rent of £1 and one bottle of whisky.
[citation needed] This theory had its first outing at the Association of American Law Professors' annual conference in late 1967 and was first alluded to in print in Macneil's article "Whither Contracts?"
The extent to which the actual doctrinal law harmonises with these norms can arguably determine the usefulness of legal tools and interventions in exchange relations, but it is a complicated question.
A symposium on relational contract theory was held at Northwestern University in 1999, with papers given by a number of American contract scholars including Stewart Macaulay,[15] Melvin Eisenberg,[16] Jay Feinman,[17] Eric Posner,[18] Robert E. Scott,[19] and Richard Speidel.
In particular, David Campbell[23] has published an edited collection of Macneil's relational contract theory work.