It's very rare for Jewish funerals to have an open casket. In other cultures, viewing the body may be important--to give a sense of closure to mourners. In Jewish culture, public viewing of the dead person is too one-sided and seems like a violation of the dead person's modesty: we can look at the body but the person can't look back. In many ways, shmirah, the burial society vigil over the body, takes the place of a communal viewing of the person's body. In the standard Jewish burial, the body is not dressed in clothing, but in a shroud, and the casket, ideally wood with no metal parts, is closed during the funeral and as the family and community members put it in the ground. The ideal is that the person's body will decompose. Traditional Jewish burial is consonant with the principles of "green burial." Some Jews believe that decomposition is the final step in the separation of the soul and the body.
The Guide to Death and Mourning for Interfaith Families is also available as a downloadable PDF and Word document.