Sir, Disability is a part of human life. Almost all people temporarily or permanently will be impaired at some point in their life. Disability is the umbrella term for impairments, activity limitations, and participation restrictions, referring to the negative aspects of the interaction between an individual (with a health condition) and that individual's contextual factors (environmental and personal factors).[1] According to global population estimates, around a billion people (15% of the world's population) live with some form of disability.[2] The world health survey results show that 785 million (15.6%) persons, 15 years and older live with a disability. Of these, the report estimates that 110 million people (2.2%) have very significant difficulties in functioning.[2] In this study, data were extracted from Statistical Center of Iran.[3] According to census results in 2011, disability prevalence is around 1.3% in Iran. The report shows that disability prevalence is more among men and increasing at older ages. In Figure 1, trend of disability prevalence have decreased from 4.09% in 1977 to 1.3% in 2011 whereas varied studies indicate that prevalence of disability is increasing globally. Because the population is aging, health services have promoted, disability definitions and categorization have changed and rate of chronic diseases and injuries resulted from accidents, natural disasters, substance abuse and conflict have increased.[4,5,6,7,8,9] Thus, the number of persons with disability has not decreased in Iran and varied definitions of disability and different methods of data collection during the time can be most common causes of the decreasing trend. Figure 1 Trend of disability in Iran from 1977 to 2011 extracted from statistical center of Iran Accurate, comparable, and accessible health care data play an important role in the planning, policy making, development and maintenance of health care services.[10,11] Internationally, methodologies for collecting data on people with disabilities need to be developed, tested cross-culturally and applied consistently. Data need to be standardized and internationally comparable to benchmark and monitor progress on disability policies and on the implementation of the Committee on the Rights of Persons with Disabilities nationally and internationally.[12] Considerable, collaborative, and responsibly efforts must be done in Iran to improve disability data. We not only need information about number of disability in Iran but also need information about their needs and required services.