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Rolling wave planning (part one) – the ebb and flow of planning major projects

Rolling wave planning (part one) – the ebb and flow of planning major projects

Author: Peter Mill, programme management consultant

How far ahead can you reasonably build a detailed plan for a large, complex programme? Six months ahead? Probably. 12 months? Hopefully. Two years? Five years? Probably not.

How far ahead should we try to plan in detail? Maybe a much shorter time-period.

The reality of critical national infrastructure programmes, whether in defence, transportation or water and energy, is that they are years long, covering lifecycles of 10 – 20 years. A period during which the macro economic and political background can go through many changes.

The very nature of these projects means they can enter untested territory, and there is sometimes no precedent or neat template plan to follow. The environment is new, the challenges are normally unique, the risks and issues will be different, and the technology will probably be novel. But how often are programmes forced to plan to the day, years in advance? This is at best a waste of effort (time and money) and at worst delusion.

As we discovered in the previous article by my colleague Nick Jacques, although we know the outcomes we desire, enterprise culture and leadership behaviours on a project frequently cause us to make decisions that solve a near term problem whilst generating a bigger one in the future.

All behaviours are defined by a combination of inputs (antecedents) and anticipated consequences. As the figure below shows, the Antecedent or Prompt, influences the behaviour to an extent. However behavioural science has shown that it is the Consequence, whether anticipated or actual that has the greatest influence on behaviour. Consequences can have varying outcomes and all are required in different circumstances. The skill is knowing how and when to influence the Consequence in order to achieve the desired behaviour.

Leadership behaviours

Consequences with immediacy and certainty consume our attention, so although people try to deliver on target and message, the demands of today’s problem trump long-term thinking and we store up problems for later. Establishing a robust plan for a long, high-value programme is intuitively and logically attractive. However, the reality is that we are generating the illusion of control.

Challenges of planning for the long-term

The world moves fast – a lot can change in a year in terms of capability, technology, and expectations. Based on my experience, I have identified the most common pitfalls of long-term planning in complex programmes:

  • Failure to understand full lifecycle requirements and the part all stakeholders play. Absolute clarity of requirements is the first step to planning, and essential prior to developing scope statements. Unless final deliverables are well understood, as they are in highly technical engineering projects, it’s inevitable some things will be left off the plan.
  • Confusing scope with work; scope is broadly non-negotiable, must be clearly defined and involve all stakeholders. Delivery work is entirely dependent on approach, capability of delivery team and funding and time available. Are we confident that we can accurately and precisely plan for activities not required to start for another three, four or 10 years? For example, mid-project we may change the approach to ‘Buy’ from ‘Make’ – completely different work, delivering the same scope. In this case, the detailed plan will be entirely different.
  • Immature estimates that add no overall value. If you are not clear on the detail of the work, estimates of time, cost and quantities will inevitably be immature and lead to funds that are misused, wasted or unavailable. The further along a project is allowed to proceed without adequate financial controls and checks in place, the higher the overall costs involved.
  • Setting unrealistic schedules that have no connection to reality. I call this the ‘crystal ball’ approach to planning. Simply setting a milestone does not automatically ensure that it will be achieved. The world moves fast, and a delivery approach envisioned at the start of a programme may be inappropriate as understanding of challenges, constraints and resources becomes clearer.
  • Insufficient relationship with uncertainty and risk. Long term projects require a greater feel and comfort with uncertainty and risk. Better to be honest about what we don’t know and use diverse expert groups to assess uncertainty and risk and model the range of outcomes.

As a result of the issues above the baseline is subject to constant revisions. These are disruptive, inefficient, and cause the project team and stakeholders to lose confidence in the plan.

Even if all the right activities have been anticipated, they may turn out to be difficult, or even impossible, to knit together once they’re completed. Watch out for the upcoming article from Costain’s chief systems engineer, Hazel Woodcock, in which she explores different project interfaces and associated boundaries, as well as steps to mitigate and manage them using a systems thinking approach.


“Managers expect they can plan for all the variables in a complex project in advance, but they can’t. Nobody is that smart or has that clear a crystal ball.”

Harvard Business Review Sep 2003

Rolling wave planning - detailed planning in the near term

As P3M professionals, we should only try to plan in detail what we can reasonably predict. Anything beyond this should remain in higher level planning packages, supporting the programme strategy and high-level objectives. This approach avoids fooling ourselves, and the programme stakeholders, that the programme schedule (for later years) is both precise and accurate.

The progressive elaboration of the detail plan is known as ‘rolling wave planning’ and I’d suggest is the most effective way to approach the planning challenge of long complex programmes. The Association for Project Management planning, scheduling, monitoring and control publication refers to this as an ‘incremental approach to planning high-density detail’.

Training courses often talk about rolling wave planning as a continuous process. As planners and project managers, we should always have a clear six to nine months of detailed plan that is continually reviewed. Near the end of the nine months we should have looked to the next horizon to detail another segment of activity and so on.

This idea of a relatively calm sea with rolling waves continually coming towards you is idyllic but is it realistic?

In reality, the calm sea is sometimes rough with unforeseen dangers that could not be planned.

Rolling wave is an approach that mitigates the challenges of planning long, complex programmes. But it isn’t a perfect solution and brings its own issues.

So – over to you…

If you’re a programme manager, I’d love to hear how you’ve overcome the challenges of creating useful baseline plans for your long programmes. Did you use a rolling wave approach, or something else?

If you’re a planner, I’d be fascinated to know how you’ve adopted rolling wave principles, but without losing sight of the integrated overall plan. Are there practices within Agile that could be usefully applied to long, complex high-value programmes?

My next article demonstrates how to apply the rolling wave concept in stormy seas and how achieving the right result for your team, your client and your organisation can be supported with rolling wave assurance.

Long and complex infrastructure programmes bring specific finance and funding cycle challenges and there are very few programme sponsors who are willing or able to fully commit funding to the full duration of the programme.

How can planning and assurance support the finance drumbeat whilst also keeping projects on track, accurate in the near and longer term?