Abstract World for Opportunistic Local Decisions in Multi-Agent Systems Using Bayesian Knowledge Bases A common solution in multi-agent systems is to commit a team of collaborating agents to a joint plan. Since any deviation from the plan by an agent is hazardous, these solutions face up to potential unplanned ``opportunistic'' actions by ignoring them, or by ad-hoc rules determining whether to accept such opportunities. Since neither of these solutions is desirable, we develop AWOL(Abstract World for Opportunistic Local decisions), an abstract framework which attempts a disciplined treatment of opportunistic action, in the context of an existing joint plan. The idea is to model the (stochastic) tradeoff of opportunism vs. continued commitment to the joint plan, while abstracting away from the state of the world. The abstract model is evaluated using strict decision-theoretic criteria, with the goal of applying the optimal decision on whether to accept an opportunistic action in the original domain. When we modeled this abstract domain as MDP, its complexity, even is lower than in a real or simulated domain, continues being high. In order to reduce this complexity, we try to implement a compact representation using Bayesian Knowledge Bases(BKB). It is a rule-based probabilistic model that allows to simply the transition probabilities in the domain. The BKB extends the well-known Bayes Network.