In certain areas, exporters are not free to decide whether or not a product should undergo modification, e.g. where government regulations or technical requirements are of overriding importance. Such modifications fall into three categories:

• Legal requirements: Minimum or special standards are often imposed by law. In addition, government regulations relating to product packaging and labelling, particularly in the case of food and drugs, can influence product modifications. For example, the mandatory declaration of certain food preservatives on the containers of food products could have a detrimental effect on consumer acceptance of the product.
• Nationalism: Governments may require that a certain proportion of components be of local manufacture. South Africa, for example, at one time required that a minimum percentage of the components of motor vehicles be manufactured locally. They may even forbid the importation of certain goods; however, this form of restriction is now discouraged.
• Technical requirements: Certain technical changes, e.g. in voltage or in the calibration of measuring instruments, may be necessary.