China and India have begun counting their people. China has started its sixth national census, while India is into its 15th. For both countries, the exercise involves enormous use of manpower, financial resources and administrative planning. Several niggling problems in compiling demographic data pose challenges for the two countries.

A census is very important for China and India both for assessing demographic developments. As the world's most populous nations, it is essential that the two capture demographic nuances. Their vast land area and diversity compel the two countries to develop their census mechanisms in manners that can capture all aspects of demographic changes. A key problem in this regard arises for migrant populations, which the two countries are trying to accommodate within their computation domains.

In China, cities like Shanghai and Beijing have quite a number of expatriate workers. So, future local government policies for city populations need to factor in expatriate workers. This is vital because local policies may have different objectives for foreign and domestic residents. Counting foreign workers effectively requires preparing a different set of questionnaire, because their backgrounds and antecedents are different from domestic workers. The census methodology needs to incorporate these additional factors, and people collecting data have to be taught and trained accordingly.