The talmudic law bal tashchit (”do not destroy”) is the predominant Jewish precept cited in contemporary Jewish writings on the environment. I provide an extensive survey of the roots and differing interpretations of the precept from within the tradition. The precept of bal tashchit has its roots in the biblical command not to destroy fruit-bearing trees while laying siege to a warring city. The rabbis expandthis injunction into the general precept of bal tashchit, a ban on any wanton destruction. Such a precept was interpreted in differing ways, along a continuum whose poles I describe as the minimalist and maximalist positions. In the minimalist position, interpreters limit the application of bal tashchit to only those situations in which natural resources and property are no longer viewed as having any economic or aesthetic worth. In the maximalist position, interpreters expand the application of bal tashchit to any situation in which nature and property are being destroyed for something other than basic human needs. Finally, I compare and contrast the substance and style of the discussion of bal tashchit from within the Jewish tradition with the contemporary discussion of environmental ethics.