Grief is a complex emotional experience or process, which is typically felt in response to the death of a loved one, most typically a family member, child, or partner. Yet the way in which grief manifests is much more complex than this. The things we grieve over are multiple and diverse. We may grieve for a former partner after the breakup of a relationship; parents sometimes report experiencing grief when their grown-up children leave the family home. We can also experience (...) grief for people we have never met. Indeed, it is not just persons that we may grieve for. People report feeling grief over the death of their pets, or about the destruction the natural environment. In all these cases one factor that seems to stand out is loss. Despite being about very different things, these various forms of grief all involve a loss of some sort. Yet there is a further aspect of grief, which, on the face of it, does not quite follow this pattern. Grief can also be experienced before a loss has occurred. Grief can be experienced while the person that one is grieving for is still living and before one has (fully) suffered the loss. This phenomenon is known as anticipatory grief. The experience of anticipatory grief is a complex phenomenon, which resists easy classification. Nonetheless, we suggest that mental time travel, our ability to mentally project ourselves into the personal past (episodic memory) and personal future (episodic prospection), is a key mechanism that underpins experiences of anticipatory grief. Anticipatory grief can still be understood in terms of loss, but it is a loss that is brought to mind through memory and imagination. (shrink)