Ecological restoration is necessary because the relationship between human society and natural systems is not as mutualistic as it should be. Although natural systems constitute the biological life support system of the planet, societal practices do not acknowledge human society's dependence on these ecosystems. The human aspiration to live sustainably on the planet must recognise that the elimination of many of the planet's species and habitats is not a sustainable practice. A necessary first step to correcting this situation is to achieve a balance between the rates of damage and the restoration of ecosystems. In other words, the anthropogenic forces destroying natural systems must be restrained and the restorative practices increased. Arguably, the most persuasive argument supporting ecological restoration is the ethical responsibility for the well-being of other life forms. Even in the unlikely event that humans could survive without undomesticated species, would they really care to do so? Additionally, humans should be making decisions not only for themselves but to benefit their descendants and to enable them to lead a quality life.

Effective ecological restoration must involve all major levels of ecological organisation from component species to entire systems. Ideally, the science should be robust at all levels; however, in a newly emerging field, the evidence base will obviously benefit from additional research. Volume 1 of the Handbook discusses ecological principles from the systems level of biological organisation to the species components. Furthermore, the dynamic aspects, including evolution, are given the attention they deserve.