A reasonable accommodation is an adjustment made in a system to accommodate or make fair the same system for an individual based on a proven need. That need can vary. Accommodations can be religious, physical, mental or emotional, academic, physical, or employment related and are often mandated by law. Each country has its own system of reasonable accommodations. The United Nations use this term in the Convention on the Rights of Persons with Disabilities, saying refusal to make accommodation results in discrimination. It defines a "reasonable accommodation" as: