Synopsis Senescence is a suicidal impulse. It is a programmed cell death occurs universally. Senescence is a genetically programmed sequence of biochemical and physiological changes. The initiation of senescence is subject to regulation by various environmental and autonomous (internal) factors. Plants have evolved mechanisms by which leaf senescence can be induced by many stresses to reallocate nutrients to reproductive organs and to eliminate water consumption by older, less productive leaves. This regulation of leaf senescence has an obvious adaptive value, allows in the plant to complete its life cycle even under stressful condition. Senescence is a correlative event and is the cumulative effect of the formation of flowers, fruits, seeds, apices and roots. Senescence is a mechanism, which works in favour of maintaining an ecological balance both for the internal milieu and the external environment of a species. The present book covers various aspects of plant senescence including ecological physiological, biochemical and molecular aspects. We have tried to cover the subject in light of current researchers.