The notion of agent’s goals is crucial in negotiation dialogues. In fact, during a negotiation, each agent tries to make and to accept the offers which satisfy its own goals. Works on negotiation suppose that an agent has a set of fixed goals to pursue. However, it is not shown how these goals are computed and chosen by the agent. Moreover, these works handle one kind of goals: the ones that an agent wants to achieve. Recent studies on psychology claim that goals are bipolar and there are at least two kinds of goals: the positive goals representing what the agent wants to achieve and the negative goals representing what the agent rejects. In this paper, we present an argumentation-based framework which generates the goals of an agent. The framework returns three categories of goals: the positive goals, the negative ones and finally the goals in abeyance.