In this chapter, I sketch an integrated account of environmental assessment, cognition, and action throughout the individual’s life span. Zimring and Gross (this volume) have already described how the schema is structured to include all three aspects; Canter (this volume) has extended this to stress the social context of meanings and actions in which these schema operate; and this chapter accepts and develops their positions. What further can a life-span approach add to the arguments advanced in these earlier integrative chapters? Liben (this volume) has already stated the case most powerfully with respect to her topic, environmental cognition; and it can as easily be applied to evaluation and action. A life-span approach enables development to be put in context: what earlier stages have so far equipped the individual to do, what the demands of the current situation are on the individual, and how variations at the present stage can affect later development. Taking this developmental perspective throws the emphasis on process and on the adaptive nature of the environmental schema for the particular life stage reached by the individual. As such, the perspective provides a test bed for examining the range of theoretical relationships between affect, cognition, and action in the environment advanced in earlier chapters. The life-span approach can also serve to reintroduce into the field a sense of the importance of individual differences, and continuities of individuality through life, which is conspicuously missing from many of the earlier chapters. The developmental tradition within psychology has not, as a whole, stressed individual differences as much as has done the life-span developmental. The life-span perspective has been much concerned with continuities and developments within the individual, as goals and tasks change over the life course. Much mainstream “developmental” research lacks this sense of continuity, being often presented as a series of snapshots of the typical child at different ages or stages. In contrast, the life-span approach, as Liben’s chapter reminds us, emphasizes the processes whereby developments occur, and conceptualizes this development as affected by biological changes, psychological development, changes in the individual’s social role and context, cultural forces, and historical changes during the individual’s life span.