‘There is nothing new under the sun’, said Ecclesiastes; and this is broadly true of inter-State arbitration (ISA), though some recent developments have perhaps thrown certain issues into greater prominence. So I shall here provide a fairly standard account of the factors which lead States to choose or refuse to arbitrate with other States. In the course of doing so, I shall allude to some issues that have recently arisen. I will consider: whether ISA is even available in a given situation; the need for consent; and the many pros and cons of this form of dispute settlement.