Dynamic Systems Development Method (DSDM)

The Dynamic Systems Development Method (DSDM) is an agile framework that originated in the mid-1990s from the principles of rapid application development (RAD).

Unlike other lighter agile methods, DSDM offers a more structured and rigorous approach, particularly suited to projects with tight deadlines and fixed budgets.

It emphasizes a strong business focus, active user involvement, iterative development and frequent delivery of operational software.

Although it aims for agility, it incorporates a degree of governance and control, which makes it attractive in corporate environments.

Its core philosophy revolves around delivering 80% of critical functionality within agreed constraints, using robust prioritization techniques.

Iterative approach with business emphasis

DSDM is fundamentally iterative and incremental, and divides the project into manageable phases and cycles.

Essentially, its driving force is business need.

Each decision and deliverable is evaluated based on its contribution to the overall business objective.

The framework includes distinct phases, such as feasibility study and business case, to ensure that the project is viable and aligned with business objectives before committing significant resources.

Subsequent phases, such as the functional model iteration and the design and build iteration, focus on incrementally developing the solution, always validating it against established business criteria.

User involvement is continuous throughout these iterations to ensure that the final product meets actual business requirements.

Prioritization with MoSCoW (Must, Should, Could, Won't)

One of the cornerstones of DSDM is its unique prioritization technique known as MoSCoW.

This acronym ranks requirements to effectively manage scope within fixed timelines and budgets:

• Must have: critical requirements for project success. Without them, the project fails.
• Should have: Important, but not vital requirements. The project can succeed without them, although alternative solutions may need to be sought.
• Could have: Desirable requirements that are less important. They will be included if time and resources permit, without affecting higher priorities.
• Will not have (this time): Requirements explicitly excluded from the current delivery timeframe, but which could be considered for future releases.

MoSCoW allows the team to ensure delivery of essential "Must Have" features, while providing flexibility with "Desirable" and "Possible" items to meet deadlines.

Principles and lifecycle

DSDM is driven by eight core principles that shape its application: 1) Focus on business needs, 2) Deliver on time, 3) Collaborate, 4) Never compromise on quality, 5) Build incrementally on a solid foundation, 6) Develop iteratively, 7) Communicate continuously and clearly, and 8) Demonstrate control.

The life cycle reflects these principles, starting with pre-project activities, then moving through the feasibility and business case phases to establish the foundation.

Basic development is carried out in iterative cycles: functional model iteration (requirements analysis and prototyping) and design and build iteration (creation of the implementable solution).

Finally, the implementation phase deploys the solution in the operational environment.

Post-project activities ensure that benefits are realized.

This structured but iterative lifecycle provides both governance and adaptability.

Summary

The DSDM method is a structured agile framework that originated from RAD. It is suitable for projects with fixed timelines and budgets.

It is iterative and incremental, with a strong emphasis on business need. User involvement is continuous to validate requirements.

It uses MoSCoW (Must, Should, Could, Won't) prioritization to manage scope. It is driven by eight principles, including "Deliver on time" and "Don't compromise on quality."