Postprocessual archaeology is not so much a coherent body of thought as a reaction against the positivist base in processual archaeology, and many of the implications of that base, such as ‘naturalism’ and ‘scientism’ - natural science taken as the model for archaeology. Postprocessual archaeology incorporates many different approaches derived from Western Marxism, hermeneutics, poststructuralism and constructivist philosophy of science. One topic of interest is social ontology - the character of social reality which may be taken as the object of archaeological study. Attempts have been made to provide archaeology with more sophisticated and differentiated conceptions of past society and to explore these conceptions through archaeological materials. Dimensions which have been theorised and explored are social power, structure, contradiction and social change, and gender. Here a key concept is agency (an aspect of social power). People are knowledgable agents - attention should be paid to intention, meaning and signification in order to understand past social phenomena. This has involved many postprocessual studies of systems of signification, and studies which recognise the social importance of symbolism and ideology. Another topic of interest is the past in the present - archaeology as a mode (one among many) of cultural production, archaeology as discourse.