This chapter focuses on existing perspectives to arrive at an integrated approach to understanding environment across time. It describes the structural components of the environment, and focuses on the core issue of conceptualizing environment across time. There is more opportunity to identify more varied components of the environmental structure, and to examine interactions among the different ecological components. When integrating the elements, the conceptual task is essentially to overlay the structure of time on the structure of environments, with particular emphasis on their human ecological importance. The chapter addresses issues of environments that varied with respect to time duration and degree of stability and change, and discusses the nonlinear time structures. Similar to the nonlinear time structures, there are numerous well-established transitions in developmental context. These differ from the prior set in that they are not repeating, but instead are generally one-time occurrences that occur regularly across most individuals.