Online help technologies range from sophisticated graphical interfaces that guide users, to proactive and intelligent tutorial interactions. Introducing ready, able, and willing human helpers in help scenarios has proven to be an important milestone in help technologies. In this paper we argue how techniques of mixed-initiative interactions can be successfully deployed in online help. We contend that a well-defined context, that encapsulates the relative knowledge, preferences, and task goals of the helper and the helpee, is integral to the success of mixed-initiative help interactions. We present empirical results to highlight the need for context-awareness in help scenarios and argue how such contexts dynamically regulate the contributions of the conversants, the helper, the helpee, and the help system, in mixed-initiative interactions.