Case Study: DSDM Bridges the Gap Between PRINCE 2 and XP

Posted by Deborah Hartmann Preuss on Oct 06, 2006

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Process & Practices,

Architecture & Design

Topics

XP ,

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PRINCE ,

Complementary Practices ,

DSDM

PRINCE 2 is a traditional project management method, mandated for government agencies and their contractors in the UK, and used by United Nations organizations for projects worldwide.  Is it possible to get Agile with such heavy methods irrevocably in place? Practitioners of the DSDM methodology have been bringing Agility to PRINCE organizations for quite a while... and this case study shows how they are stretching the method even further, incorporating Extreme Programming engineering practices.

PRINCE 2 is a  widely used standard for project management.  It is owned by the Office of Government Commerce in the UK, but is available in the public domain and free to use.  It covers management activities required to initiate, execute and close down a project effectively, and is supplemented by eight  'disciplines' of project management addressing issues such as quality, risk, business case and change control (this pdf graphically lays out the components of the methodology in an amusing way).  While it apparently has a pragmatic "use it only if you need it" approach, PRINCE 2 is generally considered to be at the heavy end of the PM methodology continuum.  Take, for example, this excerpt from a practitioner's website, describing one discipline of the methodology:

Controlling a Stage This process is where the PRINCE 2 project manager (PM) does his day job. Essentially, three major groups of tasks need to be carried out: those where the PM authorises the work to be done either by internal staff or external subcontractors, assesses the progress of this work, and accepts completed work back via a formal work package link to the Managing Product Delivery process. those where the PM reviews the status of the current stage, takes corrective action where necessary, and reports status in highlight reports to the Project Board, those where the PM captures, examines, deals with and if necessary escalates project issues to the Project Board. This process won't happen until the project board authorises a stage following initiation of the project or following the Managing Stage Boundaries process. ( from http://www.projectperformance.co.uk/prince2_tour.php )

With its authorizations, stages, and processes, this definitely looks like traditional "heavy" project management. 

Extreme Programming (XP), on the other hand, is considered one of the lightest of the Agile approaches for managing the work of software developers, fostering and relying on team-self management.

So, it seems odd to find XP and PRINCE 2 together in the same case study, but a little googling reveals that DSDM practitioner Barbara Roberts is not the only one working to reconcile these two.  This case study gives us a look at how one such project used the Agile methodology called DSDM to bridge the these two diametrically opposed approaches.

DSDM (Dynamic Systems Development Method) is another European standard, for user-centred business development. It is owned and collaboratively developed by the membership of the not-for profit DSDM Consortium, and was recently made available for free public viewing, though commercial use requires certification.  DSDM was built with full knowledge of the PRINCE project organisation and was aligned with its structure, but goes further, also defining more technical roles.  On the other hand, DSDM was also represented by Arie van Bennekum at the creation of the Agile Manifesto in 2001.  So, DSDM seems uniquely placed to fill the gap between PRINCE 2 and XP.

We asked Jennifer Stapleton, a leader in the development of the DSDM method, about how they manage projects. Here is her description of DSDM's management approach:

DSDM has always focused on team self-management but has a more formally defined wrapper around the individual teams within a project.  DSDM teams are given objectives and quality criteria to achieve and how they get there is up to them.  They are self-managing within limits, e.g. they can change their methods of creating/testing a piece of software but not the budget for doing the work – the criterion for excellence in teams is the ability to repeatedly meet the objectives with the required quality and within the given timeframe.

Back to Barbara Roberts: in her DSDM Timebox article, she explains how Prince2, DSDM and XP were layered within one project:

• PRINCE 2 provided the overall Project Management and governance processes,
• DSDM was used as a wrapper for XP to provide process and control within PRINCE 2,
• Selected XP techniques were used within DSDM for software engineering aspect of delivery

Roberts notes that the combination of DSDM and XP is already a tried-and-tested approach, however "when using such a combination of approaches it is important to be pragmatic, to ensure that the interfaces between methods are clearly understood, and that any overlap or inconsistency is addressed."

So, for example, when using DSDM with XP, there is an inconsistency in the use of the term “Iteration” – in DSDM, an iteration is the cycle of events that happen within a timebox, in XP an iteration is what DSDM would call a timebox. In the Case Study organisation, when inconsistencies arose it was agreed to use the DSDM terminology in preference to XP. This meant that XP experts had to get used to saying “Timebox”, rather than “Iteration” and to use the word “iteration” in its DSDM sense but within a week or so, the value of having a single clear set of terminology and definitions was recognised. And apart from a few minor terminology issues, DSDM with XP provides an excellent solution.

Similarly, when combining DSDM with PRINCE2, it is important to clarify exactly what in DSDM will be treated as a PRINCE 2 stage. If the wrong decision is made, the formality of PRINCE 2 is at risk of compromising the inherent agility of DSDM. So typically, you do not treat each timebox as a separate stage but rather each increment. In the Case Study organisation, this decision also needed to be reflected in the Quality Gate process – ensuring that the quality gates and Prince stages provided the correct balance of control and agility.

For those using PRINCE and interested in exploring the Agile approach to software development, it may be worthwhile to check out the upcoming Agile Business Conference, organized by the DSDM Consortium and sponsored by, among others, the Agile Alliance.

Roberts welcomes feedback on her article.