Introduction: The article contributes to conceptual studies of information behaviour research by examining the conceptualisations of information seeking and related terms such as information search and browsing. Method: The study builds on Bates' integrated model of information seeking and searching, originally presented in 2002. The model was slightly elaborated, resulting in the identification of four main modes of information seeking: (i) active seeking and searching, (ii) browsing and scanning, (iii) passive monitoring, and (iv) incidental acquisition of information. The study draws on the conceptual analysis of fifty-two key articles or books characterizing the constituents of the above modes. Results: The main activities constituting active seeking and searching are the identification, selection, location and accessing of information. The mode of browsing and scanning is based on the selection and sampling of information sources. The core activity of passive monitoring is the recognition of potentially relevant sources, while the mode of incidental acquisition of information is based on passive reception of information in certain events or situations. Conclusions: Information seeking is a multifaceted phenomenon, the research of which has led to conceptual multiplicity. The present study helps to create an overview of the multiple viewpoints by specifying the conceptual space of information seeking phenomena.