The persistent difficulty in conceptualizing the relationship between addictive and other mental disorders stands out among the many challenges faced by the field of Psychiatry. The different philosophies and schools of thought about, and the sheer complexity of these highly prevalent clinical conditions make progress inherently difficult, not to mention the profusion of competing and sometimes contradictory terms that unnecessarily exacerbate the challenge. The lack of a standardized term adds confusion, fuels stigma, and contributes to a "wrong door syndrome" that captures the difficulty of not only diagnosing but also treating addictive and other mental disorders in an integrated manner. The World Association on Dual Disorders (WADD) proposes the adoption of the term "Dual Disorder" which, while still arbitrary, would help harmonize various clinical and research efforts by rallying around a single, more accurate, and less stigmatizing designation.