Political anthropology concerns the structure of political systems, looked at from the basis of the structure of societies. Political anthropology developed as a discipline concerned primarily with politics in stateless societies, a new development started from the 1960s, and is still unfolding: anthropologists started increasingly to study more "complex" social settings in which the presence of states, bureaucracies and markets entered both ethnographic accounts and analysis of local phenomena. The turn towards complex societies meant that political themes were taken up at two main levels. First of all, anthropologists continued to study political organization and political phenomena that lay outside the state-regulated sphere (as in patron-client relations or tribal political organization). Second of all, anthropologists slowly started to develop a disciplinary concern with states and their institutions (and of course on the relationship between formal and informal political institutions). An anthropology of the state developed, and it is a most thriving field today. Geertz' comparative work on "Negara", the Balinese state is an early, famous example.