This article explores a solution to the choice-of-law issues concerning both voluntary and involuntary assignments arising in a domestic forum. The focus is on English private international law rules relating to cross-border assignments. A distinction is made between primary and extended parties as the foundation for choice-of-law analysis. Drawing on insights from the distinction of the use value and exchange value of debts found in economics, this article proposes a new analytical framework for choice-of-law based on a modified choice-of-law theory of interest-analysis.