In the past decade, various investigators have attempted to find new pharmacological agents for the treatment of obsessive disorders. Of these, the drug which has attracted attention and has been most promising is clomipramine. This paper attempts to review the usefulness of clomipramine in the treatment of obsessive disorder. Accidentally, it was discovered that clomipramine was effective in alleviating obsessive symptoms in depressed patients by a Spanish psychiatrist, Lopez-Ibor. Initial studies carried out mainly on patients with major depression reported that obsessive symptomatology benefited with clomipramine therapy. A number of uncontrolled and controlled studies confirmed the efficacy of this drug in obsessive neurosis. The drug improves the obsessive symptoms. Discontinuation of the drug is followed by a relapse. The efficacy, dosage, duration and side effects of treatment with clomipramine are discussed in this paper.