In the human sciences interdisciplinary research can result from two separate but interrelated needs. The first is the need for more information and data. The second is the need for more common structures, or for analytical integration.

At the first level interdisciplinary collaboration poses little problem. It involves the exchange of information among related disciplines. It may sometimes lead to the adoption of common methods by related disciplines, which in turn may pave the way for integration at the level of analysis or interpretation.

The second need, for analytical integration, is beset with difficulties. Unlike in the natural sciences, in the social sciences there is no linear order of sciences ranged between decreasing generality and increasing complexity. On the contrary, some social sciences tend to reduce diverse social phenomena to a single perspective peculiar to that science, and the sociologists' reductionism is often dubbed sociological imperialism.