The project life cycle is the series of phases a project passes through from idea to completion. Naming the phases matters because each one needs different skills, involves different people and ends with a decision: continue, change course or stop. Organisations that formalise these decisions — called phase gates or stage gates — cancel bad projects earlier and waste less money.
Phase 1: Initiation
The goal of initiation is to decide whether the project should exist at all, and if so, to define it well enough to plan.
- Clarify the problem or opportunity and the business case.
- Identify the sponsor and key stakeholders.
- Define high-level scope, objectives and success criteria.
- Estimate order-of-magnitude cost and duration.
- Identify major risks and constraints.
Key deliverable: a signed project charter.
Gate question
Is the expected value worth the cost and risk — and do we have a sponsor willing to own it?
Phase 2: Planning
Planning turns the charter into a roadmap the team can execute. The depth of planning depends on your methodology: a construction project may plan in detail for months, while an agile team plans a release roadmap and then details only the next sprint.
- Build a work breakdown structure.
- Estimate effort and duration (try PERT).
- Sequence work and find the critical path.
- Create the budget and resource plan.
- Plan risk, quality, communication and procurement.
- Agree roles with a RACI matrix.
Key deliverables: project management plan, baseline schedule and budget, risk register.
Gate question
Is the plan realistic, resourced and agreed by the people who will do the work?
Phase 3: Execution
Execution is where most of the budget is spent. The project manager's focus shifts from planning to leading: coordinating the team, managing suppliers, keeping stakeholders informed and protecting the team from distraction.
- Kick off the project and onboard the team.
- Assign and coordinate work.
- Manage quality and supplier delivery.
- Run the communication plan.
Phase 4: Monitoring and controlling
This phase runs in parallel with execution. It compares actual progress with the baseline and takes corrective action.
- Track schedule and cost (use earned value for objective numbers).
- Review and update risks and issues weekly.
- Run change control: every scope change is assessed for impact on time, cost and risk before approval.
- Report status — a one-page status report with RAG ratings works for most audiences.
Status reports should answer three questions: Where are we? What has changed? What do you need from me?
Phase 5: Closure
Closure is the phase most often skipped — and the one that stops organisations repeating the same mistakes.
- Confirm acceptance of deliverables against success criteria.
- Hand over to operations with documentation and training.
- Close contracts and release people and budget.
- Run a lessons-learned session (template).
- Celebrate the team.
Life cycle models
| Model | How it works | Best for |
|---|---|---|
| Predictive | Phases run once, in sequence | Stable scope, high cost of change |
| Iterative | Repeat phases to refine the solution | Complex solutions needing feedback |
| Incremental | Deliver usable pieces in sequence | Early value delivery |
| Adaptive (agile) | Short iterative and incremental cycles | High uncertainty |
| Hybrid | Mix of the above | Most real-world organisations |
Put this into practice
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