Interactions between agents are traditionally specified as interaction protocols using notations such as Petri nets, AUML, or finite state machines. These protocols are a poor fit with autonomous proactive agents since protocols are message-centric and do not support goals. Additionally, interaction protocols prescribe how interactions are carried out by agents, thus limiting the flexibility of the interactions. This also limits robustness, by reducing the available options for recovering from failure. In this paper we propose a goal-oriented approach to interaction. Since we aim at a useful and practical approach that can be used by practising software engineers, a design methodology is an important part of our solution. We present the Her...