Project Management 3-There is an old instruction that survives because it is difficult to improve on: plan the work, then work the plan. Almost every serious project failure can be traced back to a violation of one half of that sentence or the other — either the plan was never good enough to be worth following, or a perfectly good plan was abandoned the moment reality applied pressure. This guide covers the machinery that turns an authorised project into an executable one: the Project Management Plan, the start-up process, success criteria, scope definition and the Work Breakdown Structure, and then the full scheduling toolkit — network diagrams, dependency types, lead and lag, the forward and backward pass, critical path, float, and Gantt charts.

1. Planning and Control: Two Halves of One Job

Planning and control are the two key elements of project management, and the relationship between them is strictly sequential. In planning we examine the situation, decide what we intend to do, and work out how we intend to do it. In control we actually execute that plan. Planning is therefore the foundation of control — without a plan there is nothing to control against and no target to aim for.

The ultimate purpose of planning is to avoid or reduce mid-course changes, because too many changes produce exactly two things: time delays and cost overruns. This is not a theoretical concern. When Japanese industry set out to make its mark on the world in the late 1960s, it placed enormous emphasis on detailed, well-considered plans and on meticulous execution of those plans. The reasoning was practical rather than philosophical: in terms of resource mobilisation, following a settled plan is far less painful than keeping the plan permanently open-ended.

The project manager’s specific task at this stage is a conversion job. The Project Charter and the Business Case contain the mission, the vision and the high-level requirements. The manager takes those documents and converts them into a detailed Project Management Plan.

2. The Project Management Plan

All the detailed planning done for the various aspects of a project is integrated into a single document known as the Project Management Plan — often shortened to the project plan. It is used to control the project and it acts as the baseline plan. Once the manager and team have finalised it, it should be approved by the project’s sponsor.

A useful way to remember what the plan must establish is as six questions.

What Goes Into the Plan

The Subsidiary Plans in Detail

Once written, the plan does a great deal of work. It guides execution; documents the assumptions made during planning and the reasoning behind the alternatives selected; facilitates communication between stakeholders; defines key management reviews in terms of content, extent and timing; provides the baseline for progress measurement and control; supplies the team and management with guidelines on development phases and estimates for cost, schedule and resources; and serves as the reference point for quality expectations regarding the project’s output.

3. Project Start-Up

There is a useful distinction hiding in the vocabulary here. Project start denotes a particular point in time at which the project begins. Project start-up denotes a course of action taking place over a period. The start-up process runs from the moment the decision to proceed is made until sufficient conditions exist for efficient cooperation between participants and proper management of the project’s direction.

It is characterised, memorably, by three things: unqualified expectations, great uncertainty, and considerable time pressure. Core team members and their roles are identified, equipment is procured and staff acquired, with further members inducted as required.

The first step of start-up is to finalise the plan and establish the baseline — a plan that has been finalised and approved, then taken as the base for execution so that subsequent changes are not random but flow through the change control process. The plan is finalised by the Steering Committee; resources are committed; and final approval may be required from the project manager, the Steering Committee and user management. Where contractors are involved, the prime contractor and the procurement agency may also need to sign off. Steering Committee approval represents a commitment to implement the project strictly as planned — a commitment to scope, schedule and budget simultaneously.

What Start-Up Delivers

Two further start-up activities are worth noting. On staffing, the manager negotiates which personnel are assigned and when they will be available, evaluates their skills, competencies and training needs, assesses any risks in using the staff assigned, and ensures new personnel are properly briefed on their roles. On team review of requirements, every team member benefits from reading the requirement documents and the plan so as to understand the full scope of work — usually handled through a kick-off meeting, with regular orientation meetings on larger projects. The objectives are to review system specifications, milestones, procedures and standards, to build an understanding of the whole system before work begins, and to develop genuine buy-in and ownership of the end product.

4. Success Criteria and Key Performance Indicators

Success Criteria are the qualitative and quantitative measures used to judge whether a project succeeded. A project is considered successful when the value achieved against these measures exceeds a predefined hurdle rate, either during execution or at completion. They are unique to each project, they should be discussed and clearly stated in the initial phase — doing so measurably increases the probability of success — and they should be reviewed at the end of every phase to confirm they can still be met.

The traditional view held that a project succeeded if it finished on time, within budget, and met the required quality criteria. That is no longer considered sufficient. Stakeholders now weigh many other factors, and critically, different stakeholders apply different success criteria to the very same project.

Because these views diverge, the success criteria must be clearly defined with all stakeholders before the project begins. A further complication: stakeholders apply different time horizons when judging success — some assess at the moment of completion, others years afterwards.

Key Performance Indicators are the values of the success criteria that can be measured as the project progresses, allowing corrective action to be taken in time. They serve to gauge the likelihood of success while there is still opportunity to influence it, rather than delivering a verdict after the fact.

5. Scope: Philosophy, Planning and the Statement

Scope defines the total work required to execute a project and is the constraining factor within which the project must perform. In every project it has two distinct aspects: what the project is to deliver — the product or service deliverables, the objective — and the work that must be done to deliver it successfully.

Defining scope means capturing the client’s requirements and being explicit about what is included and what is not. That second half is routinely neglected and routinely expensive: a misunderstanding about deliverables can create havoc and disputes during execution or at closure. The product or service is broken into components and sub-components for clarity in what is called the Product Breakdown Structure (PBS).

What Scope Planning Produces

Scope planning is carried out to develop a written scope statement, which becomes the basis for all future project decisions. The actual scope is progressively elaborated and documented as more detail about the deliverables emerges. The scope statement must identify both the objectives and the deliverables, and it must include the criteria that will be used to determine whether the project or phase has been completed successfully. In effect it acts as an agreement of understanding between the project team and the customer.

The sequence is macro before micro: broad, high-level planning first, detailed planning afterwards. Scope planning also draws on the Project Charter and on the constraints and assumptions relevant to implementation — and that list of constraints and assumptions is not static, so it must be kept current throughout the life cycle.

Comprehensiveness matters here for two specific reasons: initial scope planning becomes the basis for all subsequent detailed planning, and a small error introduced at this stage magnifies many times over as the project progresses. The correction path is always longer than the original path — an error introduced early is typically detected considerably later, by which point extra work is needed simply to return to where you should have been.

A separate Scope Management Plan should be drawn up describing how the total scope will be managed and controlled, and specifically how changes to scope will be identified, defined, classified, documented, managed and integrated into the project. The detailed Scope Statement is revised and refined as work progresses — but the manager and team must ensure that only approved changes are updated into the plan, and that every approved change is fully documented for future reference.

6. The Work Breakdown Structure

The WBS is the single most important structural tool in the planning toolkit. Tasks are divided into sub-tasks, which are decomposed further into more sub-tasks at increasing levels of detail until a task-oriented family tree exists. The number of levels depends on the complexity and size of the project, and the guiding aim is that tasks are broken into manageable packages.

WBS Levels and Numbering

Deciding how many levels to use is a judgement call with a clear test. Too many levels make control and execution cumbersome; too few prevent proper assignment and control. The test is this: can you develop cost and duration estimates at this level? If not, decompose one level further and ask again, repeating until the answer is yes. The level of detail reached should allow each task to be assigned and delegated to a specific department, team or individual.

Two structural rules govern the tree. Each level has a parent-child relationship: a parent task finishes only after all of its children are complete, and each parent should have more than one child for the breakdown to be meaningful. And each task should have at least one clearly defined, measurable deliverable, so there is never any doubt about whether it is complete.

Drawing the WBS

The WBS should be produced very early. It is drawn by the project team from their collective experience, supplemented by brainstorming with other stakeholders to surface every possible task. The first draft will almost certainly not capture everything, so it must be reviewed repeatedly, with missing activities added each time. This progressive refinement as the project becomes clearer is known as the rolling wave effect.

Why the WBS Earns Its Central Position

The Work Package

The work package is a group of related tasks defined at the lowest level of the WBS, and it is the level at which the project is actually managed. Each work package is further broken into activities for the network that can be budgeted, defined, scheduled and controlled. Each has scheduled start and finish dates and a budget assigned to it, time-phased across its duration. Each is distinguishable from every other, and each should carry a narrative description of the scope of effort so the work is unambiguous. A work package either has a limited duration — roughly 80 hours is the usual guide — or it can be divided into measurable milestones. Work package schedules are then integrated with higher-level schedules.

7. Project Network Diagrams

Delivering on time and within budget without compromising quality is the permanent challenge, and optimal scheduling of activities plays a decisive role in meeting it. Project networks are the basic tool for detailing every activity required, sequencing them properly, and drawing them as a connected series so that the minimum total project duration can be calculated and progress monitored against that target.

Before drawing anything, it helps to be precise about what an activity is. Within a project an activity is the lowest level of effort that consumes time and resources; it has a definable start and finish; and it performs a part of the total work package. On the perennial question of whether a task differs from an activity, there is no consensus in the profession — some application areas treat activities as composed of tasks, others treat tasks as composed of activities, and many treat them as interchangeable. The practical position is that the terms are interchangeable and the context is what matters.

Two Methods of Drawing the Network

8. The Four Dependency Types

Take two activities, A and B, where B depends on A. Activity A can either have started or have finished; on that basis B can either start or finish. Two states multiplied by two states gives four logical combinations — and those four combinations are the complete set of dependency relationships available in project scheduling.

The naming convention is worth decoding once and remembering. The first letter describes the position of the independent activity A. The second letter, after the hyphen, describes the dependency of activity B. S stands for Start and F for Finish.

Lead and Lag

Consider pouring concrete into a mould to make a slab (activity A), then placing that slab on a column (activity B). The relationship is Finish-to-Start, but there is a complication: the mould must be left for a day to dry before the slab can be used. There are two legitimate ways to model this.

A lag introduces waiting time into a dependency. A lead does the opposite — it allows a successor to begin before its predecessor has fully completed, overlapping work that would otherwise be strictly sequential. Both are legitimate scheduling devices, and both change the calculated project duration, so both must be applied deliberately rather than casually.

9. Critical Path Analysis

The Critical Path Method was developed in the 1950s by Remington Rand and DuPont as a tool for improving management control of maintenance projects. It is now used universally — construction, software, R&D, engineering, product development. To arrive at a critical path you need three things: a list of all activities required, the duration of each, and the dependencies between them.

CPM works by sequencing activities in a logic diagram, then running two calculations across it. The forward pass computes each activity’s early start and early finish, working left to right through the network. The backward pass computes each activity’s late start and late finish, working right to left from the project end date. The difference between these two sets of dates gives each activity’s float — and the activities with the least float form the critical path.

Float and Its Two Formulas

Float, sometimes called slack, is the margin by which an activity can be delayed without pushing out the project end date. Take an activity whose early start is week 1 and whose late start is week 6. It can begin as late as week 6 rather than week 1 with no negative impact on the project’s finish date — it therefore carries five weeks of float.

There is a subtlety that catches people out. If two consecutive activities B and C each show five weeks of float, that does not mean each can be delayed by five weeks independently. The float is shared along the path. Suppose B starts two weeks late because the assigned person was on leave. B’s duration is two weeks, so it now finishes in week 5 against a late finish of week 8 — leaving three weeks of margin, which passes to its successor C. C still has float, but the original five weeks has become three, because B consumed two of them. Float is a pool handed down a chain of activities, not a private allowance belonging to each.

Positive, Zero and Negative Float

Consider one project of eight activities, A through H, where the network calculates a duration of 20 weeks and the critical path runs A–E–G–H. Now vary only the imposed end date and watch what happens.

The point common to all three scenarios is that the critical path activities do not change. A–E–G–H remains the longest path through the network regardless of what date is imposed on it. What changes is the float carried by that path — zero, positive or negative. The critical path is defined as the longest path with the least float, and it keeps that identity even when the least float happens to be a comfortable four weeks.

10. The Gantt Chart

Over the past two decades arrows linking the bars have been added to Gantt charts to show dependencies, and project management software now displays those interdependencies automatically, letting you see how a delay in one activity ripples into others. A word of caution though: where too many links are present, the chart becomes difficult to decipher, which defeats the purpose entirely.

Floats are usually depicted as a single line drawn after the bar, so an activity with slack looks visibly different from one without. The important operating rule is that a Gantt chart is generally used for summary-level activities. For the details of individual activities and the logical dependencies between them, you must go back to the network.

What to Take Away

Every technique above serves a single purpose: converting a general intention into a set of specific, assigned, estimated, sequenced commitments that a team can actually execute and a manager can actually control. Get the scope right and the WBS complete, and the schedule largely builds itself. Get them wrong, and no amount of network analysis downstream will rescue the project.