Background: Psychiatric community stud- ies are essential for the planning and development of psychiatric services, as well as being helpful in examining the socio-demographic correlates of mental disorders in a given community. Few such studies have been carried out to date in the Arabian peninsula. This paper forms part of a multipurpose community psychiatric survey conducted in A1 Ain in the United Arab Emirates. The findings regarding lifetime prevalence and psychiatric morbidity are reported. Methods: A total of 1394 (n= 1394) adults systematically sampled from Al Ain community were assessed with a modified version of the Composite International Diagnostic Interview (CIDI) as well with other instruments: the new screening psychiatric instrument, Self-Reporting Questionnaire (SRQ-20), and the Structured Clinical Interview for DSM-IV Axis 1 disorders (SCID) screening module. Lifetime prevalence and 1-week prevalence rates of mental distress as measured by screening instruments were estimated as well as the lifetime prevalence rate of CIDI ICD-10 psychiatric disorders. The sensitivity of the CIDI interview to correctly pick up distressed subjects, as well as those who had undergone previous treatment for a psychiatric disorder, was also calculated. Associations between socio-demographic risk factors and ICD-10 psychiatric disorder as well as with mental distress were also examined by bivariate and multivariate analyses. Results: Overall lifetime prevalence of ICD-10 psychiatric disorder was found to be 8.2% (95% CI: 6.7–9.7), while the 1-week prevalence rate of mental distress as measured by the SRQ-20 was 15.6% (95% CI: 11.8–19.5) and the lifetime prevalence rate of mental distress as measured by the new screening instrument was 18.9% (95% CI: 11.5–25.9). The CIDI interview correctly picked up 42% of subjects who had received previous psychiatric treatment and 51% of the distressed. Mood disorders and anxiety (neurotic) disorders were more common in women and alcohol and substance use disorders were exclusively confined to men. Female sex, young age, quality of marital relationship, life events over past year, chronic life difficulties, physical illness, family history of psychiatric disorders and past history of psychiatric treatment were found to be significantly associated with ICD-10 psychiatric disorder. Multivariate analysis revealed that age, sex, exposure to chronic difficulties and past history of psychiatric treatment were the most significant predictors of ICD-10 psychiatric disorders, and exposure to chronic difficulties, past history of psychiatric treatment and educational attainment were the significant predictors of lifetime ever and current mental distress. Conclusion: The pattern and trend of psychiatric morbidity found in this survey is in line with those reported by other surveys that utilized similar assessment instruments. Differences in rates are explained by different methodologies used.