The ADM is structured in a way that it supports several iterations of either the whole method, a couple of phases, or a single phase. In particular, the iterations can be the following:
1. The overall iteration passes through all eight ADM phases. Starting at the preliminary phase, moving on to the vision phase (A), and ending at the Architecture Change Management Phase (H). After that, the iteration should restart again with phase A.
2. There can also be iterations around a set of phases, such as an iteration for the architecture context, which includes an iteration of the preliminary phase and the vision phase (A). Another common iteration around a set of phases is the architecture definition iteration, which includes the phases in which the actual architecture for each layer is defined. This is done in the phases Business Architecture (B), Information Systems Architecture (C), and Technology Architecture (D). Other common iterations include the transition planning iteration including Opportunities and Solutions (E) and Migration Planning (F), as well as the Architecture Governance Iteration including the phases Implementation Governance (G) and Architecture Change Management (H).
3. Last but not least, an iteration can also just include a single phase. This can be the case if a project has a broad scope and requires an iterative approach within single phases.
TOGAF highlights that the ADM should not just be taken and applied as it is. It should rather always be validated whether it has to be adapted to the specifics of an organization. Although this is a valid point and it puts some discussions into perspective, I still believe that the standard ADM, as defined in the TOGAF Standard, should be adapted. Although I do not proclaim that my version is the best version for all, I believe that it generally has a better fit as a starting point for organizations.