Research has demonstrated that people engage in multiple types of information-seeking strategies when using information retrieval (IR) systems; unfortunately, current IR systems are designed to support only one type of information-seeking strategy: specifying queries. The limitation of the existing IR systems calls for the need to investigate how to support users as they shift from one information-seeking strategy to another in their attempts to achieve their information-seeking goals. The focus of this study is on the in-depth investigation of shifts in the micro-level of user goals-"interactive intention" and information-seeking strategies that users engage in within an information-seeking episode. Forty cases of library uses were selected from four different types of libraries for this study. The qualitative and quantitative analysis of the data identifies four types of shifts of interactive intentions and three types of informationseeking strategies. The results of the study are discussed to understand the nature of the interactive IR process, and to further suggest their implications for the design of adaptive IR systems.