An essential first step in analogy is retrieval of a source analogue appropriate for the target situation. In this paper, we focus on the phenomenon of interactive analogical retrieval (IAR) wherein the source analogues are obtained through interaction with online information environments. We first provide a descriptive account of IAR based on two in situ studies. We then describe an information-processing model (called PRISM) that provides an explanatory account of IAR. We conclude with a discussion of some of the theoretical and technological implications of this work.