Pmam kin groups can be analysed in terms of descent, as we showed in chapter 1, and certainly Ponams themselves conceptualised these groups this way, referring to kin groups as ken si ("one origin") and identifying them by the name of their focal ancestors. It is also true however, that the neostructuralist thesis that Melanesian kinship is organised in terms of principles of exchange applies to Ponam. Island kin relations often derived their content and meaning from exchange and were inexplicable except in terms of it. This was less true of kamals, though even here exchange was important, as we show in chapter 5. However, the cognatic ken sis and the relations between line-ofthe-woman and line-of-the-man that comprised them were inseparable from the realm of ceremonial exchange. These relationships had almost no content other than that of giving and receiving, reciprocity and obligation. We will describe these groups in structural terms in this chapter. However, as our historical description in the next chapter will show, the elegant logic of the sort that neo-structuralists have revealed is rather less compelling and rather less satisfactory as explanation than those neo-structuralists suggest.