Multi-level (or multilevel) governance is a term used to describe the way power is spread vertically between many levels of government and horizontally across multiple quasi-government and non-governmental organizations and actors. This situation develops because many countries have multiple levels of government including local, regional, state, national or federal, and many other organisations with interests in policy decisions and outcomes. International governance also operates based on multi-level governance principles. Multi-level governance can be distinguished from multi-level government which is when different levels of government share or transfer responsibility amongst each other. Whereas multi-level governance analyses the relationship of different state levels and interaction with different types of actors.' Multi-level governance is an approach in political science and public administration theory that originated from studies on European integration. Political scientists Liesbet Hooghe and Gary Marks developed the concept of multi-level governance in the early 1990s and have continuously been contributing to the research program in a series of articles (see Bibliography). Their theory resulted from the study of the new structures that were put in place by the EU (Maastricht Treaty) in 1992. Multi-level governance gives expression to the idea that there are many interacting authority structures at work in the emergent global political economy. It "illuminates the intimate entanglement between the domestic and international levels of authority". Multi-level governance' is a recent concept, having first entered the lexicon of political science around fifteen years ago as comparativists became re-acquainted with European integration and discovered that authority was shifting not only from central states up to Europe, but also down to subnational authorities. The first efforts to understand this were descriptive, spawning concepts that have generated an extensive literature.