Within ecologically based approaches to human development the environment is viewed as a multidimensional and structurally organized system, with person and environment contributions functionally linked and probabilistic in nature. Bronfenbrenner's PPCT (process × person × context × time) theory is used as a conceptual framework to illustrate the implications of an ecological perspective, both for understanding and studying development. Within this framework five major issues are reviewed in this chapter: (1) the structure of the human ecosystem, which encompasses the micro‐, meso‐, exo‐ and macrosystems as well as the bioecological and subjective environments; (2) major methodological implications of an ecological perspective for studying development, such as the need to study children in real world situations and to consider both environment and experience; (3) how linkages between the bioecological dimensions of process, person, context and time both structure and moderate ecosystem influences upon development; (4) statistical and measurement issues when integrating across process, person, context and temporal influences, such the need to utilize cost‐efficient ecological assessments; (5) applications of the linked PPCT dimensions to the design and implementation of intervention strategies to promote development.