Understanding the sequence in which tasks should run in a project is a key step in project planning. When tasks depend on one another, a delay in one can ripple through the entire schedule. Recent research underscores the seriousness of this issue: a Boston Consulting Group survey found that nearly half of executives reported that more than 30% of their technology projects experience delays or budget overruns.
Learning to identify and manage mandatory project dependencies in project management reduces risk. It helps projects finish on time and on budget.
In this blog post, you will learn about mandatory dependencies in project management, why they matter, how to recognise different types, and the steps you can take to plan for them.
What is a Mandatory Dependency in Project Management?
In project management, a mandatory dependency is a non-negotiable requirement. Sometimes called hard logic, this type of dependency means the next task cannot start until the previous task is complete. The opposite is a discretionary dependency, where the order of tasks can be changed if needed.
Mandatory dependencies arise from factors beyond the project team’s control.
The main causes include:
- Contracts and Agreements: Client contracts may require sign-off at milestones before work continues.
- Laws and Regulations: Legal rules, such as privacy policies or building codes, can dictate when work can begin.
- Internal Procedures: Company policies, such as regular financial reviews, mandate specific steps.
- Physical Limitations: Tasks such as waiting for a machine to finish a prototype must happen in sequence.
Because these drivers are outside the control of the project team, mandatory dependencies must be planned into the schedule from the start. Ignoring them can cause downstream delays that are hard to recover.
Why Mandatory Dependencies Matter
Mandatory dependencies can slow down even the best-planned project. In the same BCG survey referenced earlier, nearly one in five executives reported that unsatisfactory outcomes occur in more than half of their technology projects. Common culprits included poor alignment between business and technology teams, unrealistic timelines, and insufficient resources. All of these issues relate directly to managing dependencies.
Getting stakeholders involved early is one proven way to improve results. When technology leaders are involved in strategy development from the start, project success rates are higher than when they are not. Early involvement helps teams understand mandatory dependencies, such as contract clauses or regulatory reviews, and build them into the plan. Later in this guide, you will see how to facilitate this cooperation.
Types of Mandatory Dependencies
Mandatory dependencies fall into four broad categories. Each has its own drivers and requires a slightly different planning approach.
Contractual Dependencies
Contractual dependencies come from agreements with clients, vendors, or partners. For example, a contract might require the client to approve the design before development can begin. If the client takes longer than expected to review the documents, the project stalls. Another example is a service-level agreement that requires specific reports before work can continue. These dependencies often vary by project, so review contracts carefully during planning.
Legal Dependencies
Legal dependencies arise from laws and regulations. In an IT project, you may need a privacy policy in place before processing personal data. Construction projects often require permits or safety inspections before work starts. Failing to meet legal dependencies can result not only in delays but also in fines and reputational damage. Engage legal counsel early to understand applicable regulations.
Procedure Dependencies
Company procedures establish mandatory steps. For instance, an accounting department may require a monthly sign-off before any further spending. Similarly, a quality assurance team may need to run tests before a product moves to the next phase. These procedural dependencies are often recurring across projects, so build standard lead times into the schedule.
Physical Limitation Dependencies
Some dependencies stem from the physical world. A prototype might take a machine several hours or days to produce. Concrete needs time to cure before building can continue. Hardware must be delivered and installed before software can be tested. While some physical steps can be made more efficient with better equipment, many have fixed durations that must be respected.
Identifying and Planning for Mandatory Dependencies
Handling mandatory dependencies is not about eliminating them; it is about making them visible and proactively managing them.
You can follow the following steps to find and plan mandatory dependencies:
- Identify Dependencies Early: During project initiation, gather stakeholders from all affected departments. Review contracts, regulations, internal procedures, and resource constraints. Ask questions like “What must be true before this task can start?”
- Document Each Dependency: Record the dependency, its cause, and the tasks it affects in a central repository. Use clear language so everyone understands why the step is mandatory.
- Communicate with Stakeholders: Share the list of dependencies with clients, sponsors, and team members. Confirm who is responsible for each dependency and agree on timelines for approvals or deliveries. Clear communication reduces misunderstandings.
- Monitor Progress: As work progresses, track dependencies on a dashboard or Kanban board. Progress tracking is vital; BCG research found that using effective early-warning systems can increase success rates by up to 16 percentage points.
- Adjust as Needed: When a dependency is at risk of causing a delay, take corrective action. Options include re-sequencing discretionary tasks, requesting quicker turnaround from stakeholders, or allocating extra resources. Projects with fully staffed, cross-disciplinary teams have a higher success rate than those with key positions vacant, so ensure you have the right mix of skills available to respond to issues.
Practical Examples Across Industries
To make mandatory dependencies more tangible, here are examples from various sectors:
- Software Development: A team developing a mobile app cannot begin user testing until it obtains consent forms that comply with applicable data privacy laws. Testing cannot start until a test environment is set up and approved by the security team.
- Construction: Workers cannot pour a second floor until the first floor’s concrete has cured for a specified period. Similarly, electrical work cannot begin until the structural frame is inspected and signed off.
- Healthcare: Before launching a clinical trial, researchers must obtain ethics committee approval. No patient can be enrolled until informed-consent documents are finalised and the necessary supplies are delivered.
- Marketing: A campaign may hinge on the legal team approving advertising copy before it goes live. If the approval is delayed, the launch must be postponed.
Each of these examples demonstrates how mandatory dependencies safeguard quality, safety, and compliance. They may seem restrictive, but they exist to prevent bigger problems later.
Impact of Ignoring Mandatory Dependencies
Failing to account for mandatory dependencies can have serious consequences. Projects can run over budget, miss deadlines, or deliver lower quality. According to BCG’s survey, when meaningful rewards and incentives are offered for meeting timelines and specifications, success rates improve by nearly 25%. Conversely, ignoring dependencies and hoping to “catch up later” typically leads to the opposite result.
Missed dependencies also strain relationships with clients and regulators. If a contract requires client approval before proceeding and the team moves forward without it, you risk breaching the contract. If you fail to comply with a legal requirement, you may face fines or project shutdowns. Planning for dependencies is not optional—it is part of responsible project management.
FAQs
Q1. What is the difference between mandatory and discretionary dependencies?
Mandatory dependencies are non-negotiable and arise from contracts, laws, procedures, or physical limits. Discretionary dependencies are based on best practices and can be changed when needed.
Q2. How do I identify a mandatory dependency?
Review contracts, regulations, company policies, and resource constraints during planning. Ask team members and stakeholders what must happen before a task can start.
Q3. What happens if I overlook a mandatory dependency?
You risk delays, cost overruns, and legal issues. Unmet contractual or regulatory requirements can halt the project or result in penalties, so proactive planning is essential.
Q4. Can mandatory dependencies change during a project?
Yes. New regulations, contract amendments, or resource constraints can introduce additional dependencies. Monitor your environment and update your plan as needed.
Summary
Mandatory project dependencies might feel like obstacles, but they are safeguards that help deliver quality outcomes. By understanding what drives these dependencies and incorporating them into your plans, you reduce risk and build trust with clients and stakeholders. Take the time now to map out your mandatory dependencies—your future self will thank you.
Further Reading:
I am Mohammad Fahad Usmani, B.E. PMP, PMI-RMP. I have been blogging on project management topics since 2011. To date, thousands of professionals have passed the PMP exam using my resources.
