Bronfenbrenner named his original model "Ecological Systems Theory". Through this framework, Bronfenbrenner identified the need to understand individuals’ development within their environments. In order to conceptualize environmental contexts, Bronfenbrenner described four ecological systems:

Bronfenbrenner suggested that individuals constantly interact with these systems. He also stated that both individuals and their environments constantly affect one another.[3] However, in this original model, Bronfenbrenner recognized there was not enough focus on individuals’ own role in their development,[4] and thus began further developing this model.

The history of bioecological systems theory is divided into two periods. The first period resulted in the publication of Bronfenbrenner's theory of ecological systems theory, titled The Ecology of Human Development, in 1979.[10] Bronfenbrenner described the second period as a time of criticism and evaluation of his original work.[4]

The development of ecological systems theory arose because Bronfenbrenner noted a lack of focus on the role of context in terms of development. He argued the environment in which children operate is important because development may be shaped by their interactions with the specific environment. He urged his colleagues to study development in terms of ecological contexts, that is the normal environments of children (schools, homes, daycares). Researchers heeded his advice and a great deal of research flourished in the early 1980s that focused on context.

However, where prior research was ignoring context, Bronfenbrenner felt current research focused too much on context and ignored development. In his justification for a new theory, Bronfenbrenner wrote he was not pleased with the direction of research in the mid 1980s and that he felt there were other realms of development that were overlooked.[5]

In comparison to the original theory, bioecological systems theory adds more emphasis to the person in the context of development. Additionally, Bronfenbrenner chose to leave out key features of the ecological systems theory (e.g., ecological validity and ecological experiments) during his development of bioecological systems theory. As a whole, Bronfenbrenner’s new theory continued to go through a series of transformations as he continuously analyzed different factors in human development. Critical components of bioecological systems theory did not emerge all at once. Instead, his ideas evolved and adapted to the research and ideas of the times. For example, the role of proximal processes, which is now recognized as a key feature of bioecological systems theory, did not emerge until the 1990s.[4] This theory went through a series of transformations and elaborations until 2005 when Bronfenbrenner died.[6]

	Created by Amy Levin about 12 years ago

Note on Bronfenbrenner, created by Amy Levin on 10/10/2014.

Bronfenbrenner