Project dependencies: Types, examples, and how to manage

Much like a relay race, projects are often completed by passing tasks from one team member to the next. Unlike a relay race, some project tasks require other tasks to move forward before they can be started. This relationship between tasks is known as a dependency.

As a project manager, understanding how dependencies work can help you define a clear, consistent plan before initiating the project. Here's what you need to know to streamline your process, prioritize tasks, avoid bottlenecks, and manage external factors to keep your project timeline on track.

What is a dependency in project management?

A project dependency is a task that relies on another task's completion before it can begin or be completed. Dependencies define the sequence and relationships between project activities, helping teams understand which work must happen first and what can run in parallel.

General dependency examples:

• Babies are dependent on caregivers

• Plants are dependent on sunlight

• Fish are dependent on water

Examples of dependencies in project management:

• A company's PR statement is dependent on the CEO's approval of the messaging

• A reimbursement is dependent on an expense report submission

• A bug fix is dependent on the identification of its root cause

For instance, in the construction industry, pouring the foundation depends on completing the excavation. In marketing, the launch of a new product campaign depends on finalizing product design and branding.

As a project manager, tracking all dependencies ensures stakeholders know when to begin their work. Project management software with dashboards and integrations can help you manage dependencies across teams.

Examples of dependencies in software development:

• React depends on Babel for browser compatibility.

• Django depends on Pillow for image processing.

• Node.js depends on Express for web server management.

In computer science, a software dependency is a piece of software that relies on another program to function properly. These are managed through package managers like npm for JavaScript or pip for Python. Managing software dependencies is crucial for development teams using Scrum or Agile methodologies

Key terms to know regarding dependencies

Before we discuss different types of dependencies, here are some key terms to understand.

Project constraints

Project constraints are limitations or restrictions that the project manager must adhere to as the project progresses. The three main project constraints are:

• Cost: How much money can you spend to complete the project?

• Time: How long does it take you to complete a project?

• Scope: The specific goals, deliverables, features, and functions that are part of the project.

These constraints are interconnected and often referred to as the "project management triangle." A change in one constraint requires adjustments to the others. For example, increasing the scope typically requires more time or budget.

Understanding and balancing project constraints is key to successful dependency management. Project dependencies can affect all three constraints: they may increase costs, cause delays, and affect the project's scope.

Critical path

In project management, the critical path is the sequence of dependent tasks that determines the longest duration, allowing you to determine the shortest possible time to complete the project. It's a key concept when dealing with dependencies, as any delay in a critical task will delay the entire project.

The critical path method (CPM) is a project planning technique that helps you:

• Identify critical and non-critical tasks

• Calculate the expected project duration

• Visualize dependencies between tasks

A Gantt chart is a common way to visualize a project's critical path and task dependencies.

Blockers

A blocker is anything that can prevent the completion of a project activity. Blockers can be internal issues, such as a team member being out for a week, or external factors, such as an outside vendor failing to fulfill a purchase order on time. Identifying blockers early can minimize their effect on lead time.

Types of dependencies in project management

The concept of dependencies is simple, yet there are various types to consider.

Logical dependencies

Also known as causal dependencies, these are tasks that must be completed in a specific order because one task's output is required for the next. They cannot run in parallel with other tasks.

You cannot delegate a task to someone if you don't have another team member. Hiring that person is a logical dependency.

Resource dependencies

Resource-based dependencies are project constraints arising from the limited resources available to your project. If additional resources are available for the project, this dependency would not be an issue. Effective allocation of resources is key to managing these types of project dependencies.

The progress of Project B depends on a single designer finishing Project A so they have the bandwidth to complete Project B without getting overworked.

Preferential dependencies

Preferential dependencies are created by team-imposed processes but are not necessarily required for a project to be completed.

An editor may require one final review before sending an article to publish. While this step ensures there are no mistakes, it isn't strictly necessary for the project to be completed.

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External dependencies

External dependencies are tasks that rely on outside factors you or your team cannot control, such as vendor deliveries, regulatory approvals, or third-party services. Internal dependencies are more common because they involve factors your team can manage directly.

Example: A chef's menu depends on an orange shipment, but an unexpected frost delays delivery. The chef was externally dependent on the vendor, and identifying this early allows for risk mitigation and contingency planning.

Types of task dependencies in project management

Some dependencies are specific to the two tasks involved. Here are the four types of task dependencies:

• Finish to Start (FtS): This is the most common task dependency. Task B cannot start until Task A is complete, which is typical in Waterfall project management.

• Finish to Finish (FtF): Task B cannot finish until Task A is also completed. This is common with parent tasks that have subtasks, and if the subtasks aren't done, you can't complete the parent task.

• Start to Start (StS): Task B cannot start before Task A starts. These tasks run in parallel. For example, a social media marketer posts an announcement just as a web developer pushes a sales page live.

• Start to Finish (StF): Task B must start for Task A to be completed. For example, a support representative cannot leave until another representative arrives to take over.

How to identify project dependencies

Identifying dependencies early is essential for building a realistic project schedule and avoiding unexpected delays. Here's how to systematically uncover dependencies in your project:

1. List all project tasks: Document every task required to complete your project. This task list serves as the foundation for identifying which tasks depend on others.

2. Determine task relationships: For each task, ask: Does this require another task to be completed first? Can it run in parallel, or must it wait?

3. Categorize your dependencies: Classify relationships by type (logical, resource, preferential, or external) to understand which are mandatory and which offer flexibility.

4. Map dependencies visually: Use a dependency matrix or network diagram to visualize task connections and spot potential bottlenecks.

5. Validate with your team: Review your dependency map with team members. They may identify relationships you missed or suggest more efficient sequences.

Benefits of managing project dependencies well

Effective dependency management not only benefits the project but also the project manager and the team. Here are some key advantages:

Project benefits:

• Reduced delays: Fewer bottlenecks and schedule disruptions

• Better resource use: Optimized allocation across tasks and teams

• On-time delivery: Increased chances of completing projects on time and within budget

• Clearer communication: Improved coordination among team members

Personal and team benefits:

• Stronger skills: Enhanced problem-solving and decision-making for project managers

• Better collaboration: Improved team productivity and alignment

• Growth opportunities: Team members develop new skills and take on more responsibility

• Job satisfaction: Greater sense of accomplishment upon project completion

By understanding and managing dependencies well, project managers can lead their teams to success while also fostering personal and professional growth.

Tips for dependency management

Dependency management can seem overwhelming at first glance, but learning how to navigate it can set your projects up for success. Here are four tips to help you manage task dependencies effectively.

1. Organize tasks using project management software

Finding the right project management tool that works for your team can change the game when it comes to internal dependencies. Using a task management tool that can house your project plan and project activities, and clearly identify dependent tasks, can help your team stick to the project schedule. Look for tools with integrations with your other core systems.

2. Visualize dependencies clearly

Visualizing dependencies is an easy way to better understand what tasks need to be completed and in what order. Using visual tools like a Gantt chart or a Kanban board can clearly show your team members which stage your project is currently in and which tasks depend on it.

3. Monitor potential risks in a project plan

When you're establishing a project plan, brainstorm all potential internal dependencies that you may encounter during your project. Do any of your team members have a heavier workload than normal? Are you working with any external vendors to complete this project?

You cannot monitor every single potential risk, but you can keep an eye on dependencies to ensure deliverables stay on track. This is especially important for cross-team dependencies, such as when the marketing team is waiting on assets from the design team.

4. Encourage stakeholder engagement

There's no such thing as over-communication when it comes to task dependencies. If one project stakeholder knows that a task is delayed, encourage them to communicate with the entire team so individuals can adjust their timelines accordingly.

Manage your dependencies with confidence

Understanding and managing project dependencies is essential for keeping your projects on track and your teams aligned. With the right tools and processes in place, you can identify dependencies early, communicate them clearly, and adjust your plans when needed.

Ready to take control of your project dependencies? Get started with Asana to visualize your workflows, track task relationships, and keep your entire team moving forward together. Want to learn more? Explore our project management resources for additional tips and best practices.

Frequently asked questions about project dependencies