This article considers fragmented property systems – the phenomenon of contested, separated or overlapping sub-systems within a national property jurisdiction. One example is circumstances of property despite law. Globally, as many as a billion people claim de facto property without recognition by law in urban informal settlements and agro-pastoral or forested areas. Another example is property without transition to law. Many households in the developing world regulate land markets through local mechanisms notwithstanding opportunities or requirements to use law.

The article provides a conceptual frame for the emergence of property system fragmentation based on the private coordination of property relations. The article argues that fragmentation emerges in complex property systems where law attempts to displace property coordination mechanisms, but fails to induce a critical mass of property participants to alter coordination strategies. A focus on coordination provides a means to combine the methodological individualism of economic narratives with collective variables highlighted by other perspectives on property such as anthropology and complex systems theory.