Each time a teacher or a learner interacts with an Open Educational Resource (OER), these interactions produce data. This "interaction data" includes "artifact data" routinely captured during any online interaction by Web server logs (e.g., users' browsers, users' IP addresses) and "social data" created during Web 2.0-style interactions with resources (e.g., tags, comments, ratings, favorites). Interaction data can serve a number of purposes in a period of increased interest worldwide in OERs quality and uptake. First, interaction data is a valuable source of analytics about OERs and typical audience profiles. Second, combined with metadata, interaction data can enhance searching, ranking, and recommendations of learning resources. However, obtaining this data is not always easy since OERs, in particular, are generally dispersed among different systems where the interactions between resources and their users take place. This paper describes approaches to unlocking, collecting and aggregating this interaction data.