My research focuses on economic sociology and social theory. I am particularly interested in algorithmic trading and its consequences for financial markets and have been doing fieldwork (interviews and ethnographic observations) for several years, in part as the PI of the ERC-funded research project “Algorithmic Finance.” This work has sparked an interest in the role of AI and machine learning, where I am particularly concerned with discussions around ML opacity and “Explainable AI” as well as what AI/ML technologies mean for society and sociological theorizing. Another research strand is crowd and collective behavior, in particular sociological theorization on this topic. Work on this topic led to my award-winning book, The Politics of Crowds: An Alternative History of Sociology (Cambridge UP, 2012). A more recent book, Social Avalanche: Crowds, Cities and Financial Markets (Cambridge UP, 2020), combines my interests in financial markets, including algorithmic trading, and crowd and collective behavior as well as it ties these topics to another long-standing interest of mine, cities and architecture.