We describe a program for assigning correct stress contours to noun compounds in English. It makes use of two kinds of knowledge: idiosyncratic knowledge about the stress behavior of various compound types and general knowledge about English stress rules. As an example of the first, place names such as Madison AVENUE generally have rightward stress, but the word street induces left‐hand stress: MADISON street. Semantic relations between the component nouns are also important: We know that, if the left‐hand member is a grammatical object of the right‐hand member, stress is leftward (DOG catcher). Our program makes use of such idiosyncratic knowledge in determining stress by deducing the type of compound and the likely relations between the members. As an example of the second kind of knowledge, our program knows the “rhythm rule” whose consequence is that while stress in Tom PAINE is on the right, stress in TOM Paine AVENUE is stronger on Tom than on Paine. The obvious importance of such a program to speech synthesis is discussed.