Robin James Smith is Senior Lecturer in Sociology at Cardiff University, UK. His research is concerned with the ethnomethodology and ethnography of interaction in public space and mobile embodied practices. His work is influenced by, and contributes to, developments in the analysis of categorisational practices. He has also published on qualitative research methodology more generally and is the current editor of Qualitative Research and associate editor of SAGE Research Methods Foundations. He is co-editor of Urban Rhythms: Mobilities, Space and Interaction in the Contemporary City and The Lost Ethnographies: Methodological Insights from Projects That Never Were. Richard Fitzgerald is Professor of Communication at the University of Macau, China (SAR). He has researched and written extensively on methods of qualitative discourse analysis with a particular focus on membership categorisation analysis (MCA) and ethnomethodology. His recent publications on MCA include Advances in Membership Categorisation Analysis, with W. Housley, and a co-edited issue of the Journal of Pragmatics with S. Rintel and W. Housley under the title Membership Categorisation Analysis: Technologies of Social Action. William Housley is Professor of Sociology at Cardiff University, UK. He has published extensively on qualitative and social research methods, sociological theory, the study of practical reason, ethnomethodology, membership categorization analysis, social interaction and digital sociology. He is co-editor of Advances in Membership Categorisation Analysis with Richard Fitzgerald.