This paper presents a formal specification that
structures a framework in Zachman's Enterprise Architecture Model
as a tree of frames.
Each frame is the familiar
role × interrogative grid.
Each cell of the grid contains, recursively, additional frames
down to leaves.
The formalism also provides mechanisms for connecting framework
components down the recursive levels of detail and down the
grid categories of roles.
While the tree of frames expresses the structure of a framework
model, these connections express the framework's meaning.
On top of the basic formalism, additional mechanisms facilitate
customizing of framework meta-models,
viewing frameworks from different perspectives, and
imposing constraints on the framework model.
The paper also discusses implications of the formalism
on the ways in which Zachman framework models are discovered.