Our short- and long-term context defines who we are and what we’re interested in. Furthermore, when we can automatically identify others who have a similar contextual makeup and group them together, a powerful form of personalized recommendation is possible as we search and browse. As we go about their daily lives, our context changes. While engaging in projects at work, taking up new hobbies, attending events, using apps and searching on particular topics, these activities reflect our interest profiles. Some interests are long-lived, such as an interest in science, a career in a particular field or an artistic hobby. Others are more short-lived, such as attending an art exhibition, listening to a talk at a conference, frequenting a store or executing a Web search. Short-term interests can often be connected to long-term interests (e.g. listening to a talk at a conference is usually linked to a long-term interest such as a career), and in general we can characterize both short- and long-term interests as elements of a person’s contextual makeup.