Introduction: Serendipitous or accidental discovery of information has often been neglected in information behaviour models, which tend to focus on information seeking, a more goal-directed behaviour. Method: This theoretical paper seeks to map the conceptual space of serendipity in information behaviour and to arrive at a definition. This is done through carrying out a literature review on information behaviour and serendipity and defining relevant terms in the area. Using Wilson's framework as a starting point, a series of frameworks is arrived at to include serendipity in information behaviour models. Analysis: The terms used in this research space were investigated, as well as the times when serendipitous finding can occur, the dimensions of serendipitous findings, and a series of assumptions to draw out the key elements of serendipity. Results: The results of the analysis is a framework of continuums that identifies the core of this research area of serendipity in information behaviour and arrives at its definition. Conclusions: By including serendipity in information behaviour models, the frameworks arrived at should help further research in this area. A working definition of serendipity in information behaviour is a starting point for other researchers to investigate related questions in the area.