TOGAF ADM Phases A-H Explained with TOGAF 10 Agile Iteration Gantt Charts

TOGAF provides a comprehensive framework for enterprise architecture development, implementation, and operations, but its most widely recognized component is the Architecture Development Method (ADM). The popular "4A architecture" concept in China originates from ADM, though it typically only references phases B, C, and D.

ADM Phase Descriptions

Phase A: Architecture Vision

In this phase, the project boundaries, constraints, and expected outcomes are defined. Stakeholders collaboratively build an architecture vision and a Statement of Work that gains universal acceptance.

Phase B: Business Architecture

The business architecture blueprint is developed, covering both the current (baseline) and target business architectures. A preliminary gap analysis is performed between the two.

Phase C: Information Systems Architectures

This phase addresses Application Architecture and Data Architecture. Both baseline and target architectures are created for each, followed by preliminary gap analysis. The sequence can be application-first, data-first, or parallel development.

Phase D: Technology Architecture

The technology architecture blueprint is produced, encompassing baseline and target technology architectures with an initial gap analysis.

Phase E: Opportunities and Solutions

The main task is a deep-dive gap analysis that yields concrete work packages and a project plan.

Phase F: Migration Planning

Cost-benefit analysis and risk assessment are conducted. Transition architectures and key milestones are defined, and a detailed implementation and migration plan is formulated.

Phase G: Implementation Governance

Focuses on governance and control during architecture implementation. All projects must conform to the architecture blueprint, with compliance reviews detecting and correcting deviations promptly.

Phase H: Architecture Change Management

Ensures the architecture responds to changing enterprise needs. Minor changes are handled through adjustments and maintenance; major changes trigger an assessment of whether a new ADM cycle is required to redefine the architecture blueprint.

TOGAF 10 Agile Iteration Cycles

TOGAF 10 introduces official guidance for agile iterations within ADM, defining four iteration types:

Architecture Capability Iteration

Architecture Development Iteration

Transition Planning Iteration

Architecture Governance Iteration

The standard also provides concrete Gantt charts illustrating how these iterations map onto the ADM phases over time.

Reference: The Open Group official website - TOGAF 10