Loss is an inevitable experience for humans for which grief is a natural response. Nurses must have an adequate understanding of grief and bereavement in order to be more sensitive to these painful emotions and to provide appropriate care to families who have lost someone they love deeply. This article introduces four important grief theories: Freud’s grief theory, Bowlby’s attachment theory, Stroebe and Schuts’ dual process model, and Neiyemer’s meaning reconstruction model. Freud’s grief theory holds that the process of grief adaptation involves a bereaved family adopting alternative ways to connect with the death of a loved one and to restore their self-ego. Attachment theory holds that individuals who undergo grieving that is caused by separation from significant others and that triggers the process of grief adaptation will fail to adapt if they resist change. The dual process model holds that bereaved families undergo grief adaptation not only as a way to face their loss but also to restore normality in their lives. Finally, the meaning reconstruction model holds that the grief-adaptation strength of bereaved families comes from their meaning reconstruction in response to encountered events. It is hoped that these theories offer nurses different perspectives on the grieving process and provide a practical framework for grief assessment and interventions. Additionally, specific interventions that are based on these four grief theories are recommended. Furthermore, theories of grief may help nurses gain insight into their own practice-related reactions and healing processes, which is an important part of caring for the grieving. Although the grieving process is time consuming, nurses who better understand grief will be better able to help family members prepare in advance for the death of a loved one and, in doing so, help facilitate their healing, with a view to the future and to finally returning to normal daily life.