Fast Tracking vs Crashing: Schedule Compression Techniques for PMP

Schedule Compression on the PMP Exam: Two Tools, Different Trade-offs

When a project falls behind schedule or the deadline moves forward, project managers have two primary techniques for compressing the schedule: fast tracking and crashing. The PMP exam tests both concepts extensively, including when each is appropriate, what risks they introduce, and how they affect the project's cost and scope.

What Is Fast Tracking?

Fast tracking involves performing activities or phases in parallel that were originally planned to be done sequentially. It takes advantage of the fact that some activities have discretionary dependencies — they were sequenced a certain way by choice, not by necessity.

How Fast Tracking Works

If Phase B was planned to start after Phase A finishes (a finish-to-start relationship), fast tracking changes this so Phase B starts while Phase A is still in progress. The overlap reduces the overall duration.

Risks of Fast Tracking

Increased rework risk: If Phase A's output changes while Phase B is already underway, Phase B may need to be redone.
Quality concerns: Overlapping activities may lead to incomplete inputs, causing defects.
Coordination complexity: More parallel work requires more communication and integration effort.

Key PMP exam point: fast tracking does not increase the project budget. It only rearranges the sequence. However, it only works when activities can logically overlap — you cannot fast track activities with mandatory dependencies.

What Is Crashing?

Crashing involves adding resources to critical path activities to shorten their duration. The logic is simple: more people, more equipment, or more overtime should mean faster completion.

How Crashing Works

The project manager analyzes each critical path activity to determine the crash cost and crash duration. The goal is to achieve the greatest schedule compression for the least additional cost. Activities are crashed in order from least expensive to most expensive per day of duration reduction.

Characteristics of Crashing

Always increases cost: More resources, overtime, or expedited materials all cost money.
Only effective on critical path activities: Crashing non-critical activities does not shorten the project.
Diminishing returns: Adding the fifth developer to a task does not yield the same benefit as adding the second.
May create new critical paths: Shortening one critical path activity may cause a previously non-critical path to become critical.

Comparing the Two Techniques

The PMP exam often presents scenarios requiring you to choose between fast tracking and crashing. Here is how they compare:

Cost impact: Fast tracking has no direct cost increase. Crashing always increases cost.
Risk impact: Fast tracking increases the risk of rework. Crashing increases the risk of resource conflicts and diminishing returns.
Applicability: Fast tracking requires activities that can overlap. Crashing requires activities that can absorb additional resources.
Order of preference: PMI generally suggests trying fast tracking first (no added cost) before resorting to crashing.

Exam Scenarios and Decision Logic

When a PMP question describes a schedule delay and asks for the best response, use this decision tree:

Is the delay on the critical path? If not, no compression is needed — the project end date has not changed.
Can activities on the critical path overlap? If yes, consider fast tracking first.
Is fast tracking insufficient or too risky? Then crash the least expensive critical path activities.
If neither works sufficiently, scope reduction or deadline renegotiation may be necessary — but these are last resorts.

Common PMP Exam Traps

A question may say "the project must be completed faster with no additional budget." The answer is fast tracking, not crashing.
A question may describe crashing a non-critical activity. This is a wasted effort — always check that compression targets the critical path.
A question may present both techniques as options and ask which is "better." There is no universal answer — the right choice depends on the constraints described in the scenario.

Master schedule compression with our full-access practice question bank that includes detailed explanations for every answer choice.