A single market is a type of trade bloc in which most trade barriers have been removed (for goods) with some common policies on product regulation, and freedom of movement of the factors of production (capital and labour) and of enterprise and services. The goal is that the movement of capital, labour, goods, and services between the members is as easy as within them. The physical (borders), technical (standards) and fiscal (taxes) barriers among the member states are removed to the maximum extent possible. These barriers obstruct the freedom of movement of the four factors of production (goods, capital, services, workers). A common market is usually referred to as the first stage towards the creation of a single market. It usually is built upon a free trade area with no tariffs for goods and relatively free movement of capital, workers and services, but not so advanced in reduction of other trade barriers. A unified market is the last stage and ultimate goal of a single market. It requires the total free movement of goods, services (including financial services), capital and people without regard to national boundaries. Integration phases A common market allows for the free movement of capital and services but large amounts of trade barriers remain. It eliminates all quotas and tariffs duties on imported goods from trade in goods within it. However non-tariff barriers to trade remain, such as differences between the Member States' rules on product safety, packaging requirements and national administrative procedures. These prevent manufacturers from marketing the same goods in all member states. The objective of a common market is most often economic convergence and the creation of an integrated single market. It is sometimes considered as the first stage of a single market. The European Economic Community was the first large-scale example of a common market. A single market (sometimes called 'internal market') allows for people, goods, services and capital to move around a union as freely as they do within a single country – instead of being obstructed by national borders and barriers as they were in the past. Citizens can study, live, shop, work and retire in any member state. Consumers enjoy a vast array of products from all member states and businesses have unrestricted access to more consumers. A single market is commonly described as "frontier-free". However, several barriers remain such as differences in national tax systems, differences in parts of