Karl Weick devoted more than fifty years of his working life to developing the set of ideas that have formed the sensemaking perspective. Over this period, his theorizing evolved in subtle, but significant ways, shifting in what has been described as a movement from ‘sensemaking in organizing’ to ‘sensemaking as organizing’. In this shift, the emphasis moved from action to meaning, and eventually to the integration of meaning and action. Sensemaking and organizing constitute one another and cannot be understood in isolation; both are ordering processes through which people engage the ongoing flow of organizational life. This chapter traces the development of Weick’s thinking by revisiting some of his key works, notably The Social Psychology of Organizing (1979), Sensemaking in Organizations (1995), ‘Sensemaking, organizing, and surpassing’ (2020), and the widely cited article by Weick, Sutcliffe, and Obstfeld (2005). This exploration shows that Weick is not only a pretty careful thinker, but also a complex and integrative one, capable of drawing together disparate elements of human experience. Any reading of his work must therefore remain provisional, since the sensemaking perspective continues to evolve as an open and dynamic set of ideas.