This paper presents DAOS, a model for exploitation of And-and Or-parallelism in logic programs. DAOS assumes a physically distributed memory environment and a logically shared address space. Exploiting both major forms of implicit parallelism should serve a broadest range of applications. Besides, a model that uses a distributed memory environment provides scalability and can be implemented over a computer network. However, distributed implementations of logic programs have to deal with communication overhead and inherent complexity of distributed memory managent. DAOS overcomes those problems through the use of a distributed shared memory layer to provide single-writer, multiple-readers sharing for the main execution stacks combined with explicit message passing for work distribution and management.