On the plateau area of Madagascar, the rules for ceremonial speech (kabary), and skill in it, are sources of pride and topics of great interest. The most elaborate use of kabary is in the public marriage request. This event is intended to give honor to the girl's family and to evoke confidence in the boy's family, securing an alliance between them. Conceptions of the ground rules of proper kabary are diverse. There are discussions of them before, within, alongside, and after the event. The diversity includes a broad contrast between the ‘Ancestral Way’ and the ‘New Way’. Social change, but also the interests and strategies of the two parties (the boy's family and the girl's family) are involved in choice of one of these. Crucial to the conduct and success of the event is the notion of an ‘error’. What constitutes an ‘error’ is open to dispute and the significance of particular rules varies with both the strategies of the two parties, and the way in which the event is unfolding. An overriding constraint is that the alliance which the event is to ratify be accomplished. (Speech styles and social structure; ideal speech; conflict of speech norms; performance strategies; ‘error’ in performance; emergent qualities of performances; Madagascar; Malagasy (Malayo-Polynesian).)