IT use is a primary concept that should be clarified carefully since it is a major concept in several existing IS theoretical models such as the Technology Acceptance Model, Task-Technology Fit, and IS Success model. Unfortunately, most studies define this concept too simply. This can constrain our understandings of IT impacts. Therefore, it is necessary to conceptualize IT use and explore its multiple dimensions. This research attempts to formulate a research agenda for this purpose. Using activity theory and other related theories, we propose a research framework to conceptualize IT use and a multi-item scale to measure it.