Archaeologists often take stratigraphy for granted, using it for building chronologies, recognizing various natural and cultural formation processes, and understanding relations between features and settlements. But for the last few decades there has been a subtle shift in the way that we approach stratigraphy – in terms of both the kinds of techniques that can be applied (residue analyses, micromorphology, Harris matrices and so on) and the interpretive frameworks that can be employed. Perhaps it is not stratigraphy that we are talking about per se, but rather depositional practices – the many ways in which people make and alter archaeological deposits – in addition to the different interpretive frameworks that we apply to these physical accumulations.

I am quite sympathetic with the overall goal of McAnany and Hodder's article. They are working toward a synthesis that has been building on both sides of the Atlantic that applies social theory to the interpretation of archaeological deposits, including attention to social memory, materiality, identity and personhood. There has been surprisingly little cross-citation of this work in the past despite many common methodological and theoretical goals. It was because of this lack of cross-citation in the face of common goals that William Walker and I decided to bring together a group of scholars to think about the ways in which depositional practices can be interpreted in social terms. Our initial thoughts in organizing this were to look at how deposits could be used to look at ritual practice, but this original idea was modified as we discussed our cases and realized that we were addressing issues of all social practices. Our more final goal was to understand the materiality of depositional histories and the transmission of different kinds of histories, in the ways that people engage with materials of all kinds and especially in how social memory was embedded in the deposits that we study (Mills and Walker 2008).

McAnany and Hodder have similar goals and achieve them by advocating an approach that incorporates scientific field methods for identifying the content and context of deposits with a more interpretive agenda regarding what these deposits can tell us about the social life of past people. This is a programmatic statement in which these two archaeologists bring different strengths and case studies to the table. They take a ‘from-the-ground-up’ approach – emphasizing first the history of stratigraphic analyses to point out how past approaches originally concentrated on layers (the geological approach), then on interfaces (the Harris matrix approach), and finally on objects (the behavioural archaeology approach). They suggest that all of these have had their weaknesses because they have not considered the processes by which strata were made in social terms (that is, their meaning and interpretation). McAnany and Hodder offer a new term, ‘social stratigraphy’, to refer to their approach – one that takes into account the many different social processes responsible for accumulating and cutting into layers, as well as what those activities mean.

The processes of ‘stratigraphy-making’ that they discuss include rebuilding, middening, remodelling, entombing, hiding and so on – active processes that engage the reader, placing us there at the time that the activity was unfolding. Some of them raise the surface level and some lower it, but they are all ways in which strata are laid down or cut into that relate new ‘social practices or performances’ with those that came before. They contrast these stratigraphy-making processes with palimpsests – which they define as the accumulation or layering of deposits in which there are ‘considerable gaps in time between one activity and the next’ and where the ‘earlier layers are no longer visible’ (p. 9). They imply that palimpsests are not social stratigraphy in that there is an absence of relational practices between what lies above and what lies below. Such a definition, however, belies the ways in which strata can be connected through human experiences, and especially through memory-making. For example, Joyce (2008) talks about how repeated deposits in the same place were made in Honduras where there is a separation of time and of strata between deposits that are so similar that they cannot be coincidental. Similar sets of objects were placed in spaces that were clearly of different times and where the past deposits would not have been visible. How would there be repeated deposition without the transmission of memories of where it was appropriate to place these objects? We repeatedly encounter such persistent places in the archaeological record – the locations of which are not necessarily because of continuous occupation, but because of continuities in the transmission of practices and in the memory work of people connected through their performances and practices.

McAnany and Hodder's use of the general terms for stratigraphy-making could result in a much more comparative understanding of depositional processes – a new social processual archaeology, if you will. Ultimately, however, it is not just the identification of these different activities that is important, but how they are used to understand and interpret the meaning of these processes within different archaeological contexts. Thus I see this as a two-pronged approach that necessarily incorporates a dialectic between process and history, or time's cycle and time's arrow (Gould 1987). To understand the latter, however, one needs to have a strong contextual understanding of the specific historical trajectories of each case study. If the ultimate goal is to use social stratigraphy for interpreting memory, materiality, personhood and so on, then the case studies from K'axob and Çatalhöyük need to be fleshed out to get a better picture of how these broader social processes were expressed in each society. After reading their brief examples from their own work I was left wanting to hear more about how these practices were played out in each area.

Significantly, then, in order to be able truly to apply the programme of research that is laid out in this article, there needs to be more attention paid to the particulars of a case study. As one of my colleagues, Jane Hill, is fond of saying, ‘all meaning is local’ (a linguist's version of the oft-cited archaeological phrase ‘context is everything’). In other words, without understanding the way that value is constructed in different cases we will not fully be able to apply social stratigraphy.

How do we get at these differences in value? It is here that McAnany and Hodder's concentration on strata over objects could lead to a less complete picture. Although they state that ‘it is possible to take from both the object-oriented and depositional-sequence approaches to create an interpretive method that addresses social strategies of cutting and layering strata’ (p. 7), much less attention is paid to what is placed in different layers and how. It is for this reason that studies of materiality are important for understanding how social memory as a process connects people in the past (Meskell 2004; Miller 2005; Myers 2001). These may be through connections of place, genealogies of objects, the social transmission of ideas, but they are ways in which we can construct linkages, chains or networks between people, objects and their actions. Thus, although Latour is mentioned briefly in passing, actors (including objects) are connected through their engagement in different practices (Pauketat and Alt 2005). And practices, too, have genealogies (Stahl 2008) – linked by their transmission within different kinds of activities.

Genealogies of practice should lie at the heart of what we are interested in understanding through social stratigraphy – the connectedness and meaning of actions that are inscribed through depositional histories. They need not be deliberate or intentional – a mistake that was made in earlier approaches, including those referred to as ‘structured deposits’ (Richards and Thomas 1984). As Pollard (2008) points out, all deposits are structured in some way, and the different ways that these deposits are organized can provide insight into the meaning and agency of things. It is what people do with these objects that is of interest, and in how those activities relate to past activities that we can begin to use the programme of social stratigraphy to best advantage. Structured deposition may still be an important way to think about social stratigraphy – as long as we do not force it into dichotomies of ritual/domestic or intentional/nonintentional (Bradley 2003; Brück 1999).

Thus, while I think this article has moved us closer to a synthesis of traditional stratigraphic methods and social interpretations, what I find most intriguing out of the contemporary studies that the authors call ‘social stratigraphy’ are the ways in which depositional histories are linked through the practices of both memory and materiality. Although the authors talk about social memory, there is much less attention paid to the ways in which materials themselves can be used to understand the networks of people and things – networks that are linked through memory and depositional practice.