Memory for an event is influenced by many factors including retention interval, frequency of assessment, and type of information assessed concerning the event. We examined the usefulness of observer memory for contextual information in assessing accuracy of memory for central information. Participants viewed a video of a purse being stolen and were asked questions concerning the perpetrator and surrounding context of the event, including where and when the event occurred and who else was present. Participants tested immediately after seeing the video exhibited better memory than those tested for the first time 48-hour after the event. Additionally, testing immediately after viewing the video reduced forgetting over the 48-hour delay (i.e., early testing attenuated subsequent forgetting). Moreover, memory for the context of the event correlated positively with memory of the central information (i.e., perpetrator), and memory concerning other people at the event tended to have the highest correlation with perpetrator memory.