Understanding dependencies in project management

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 and consistent plan before initiating the project itself. Here's what you need to know to streamline your process, optimize your dependencies, prioritize tasks, avoid bottlenecks, and manage external factors to keep your project timeline on track

What is a dependency in project management?

In general, a dependency is something that relies on something else. 

General dependency example sentences:

• Babies are dependent on caregivers

• Plants are dependent on sunlight

• Fish are dependent on water

As it relates to project management, a dependency is a task that relies on the completion of a different task. 

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 is dependent on the completion of excavation. In marketing, the launch of a new product campaign is dependent on the finalization of product design and branding. 

As a project manager, it's important to keep tabs on all of your project dependencies so stakeholders are aware of when they need to begin their part of the project. Using project management software with dashboards and other platform integrations, like APIs, can help with managing project dependencies across teams and modules.

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. This is managed through a package manager like npm for JavaScript or pip for Python. Dependencies are specified in configuration files and installed when you compile or start the runtime.

Managing these 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 you can spend to complete the project.

• Time: How long it takes you to complete a project.

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

• Project constraints are interconnected and are often referred to as the "project management triangle". A change in one constraint requires a change in the others to compensate. For example, increasing the project scope typically requires an increase in cost and/or time.

Understanding and balancing project constraints is key for successful dependency management. Project dependencies can impact all three constraints; they may increase cost, cause delays, and affect the scope of the project.

Critical path

In project management, the critical path is the sequence of dependent tasks that form the longest duration, allowing you to determine the shortest time possible 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 technique used in project planning to identify the critical and non-critical tasks, calculate the expected duration of the project, and show the dependencies between tasks. A Gantt chart is a common way to visualize the critical path and task dependencies in a project schedule. 

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 not fulfilling a purchase order on time. Identifying blockers early can minimize their impact on lead time.

Types of dependencies in project management

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

Logical dependencies

Also known as a causal dependency, these dependencies are parts of a project that are necessary for a project's completion. They're often the goal output for all of the preceding tasks and cannot run in parallel with other tasks. 

For example, you cannot delegate a task to someone else if you don’t have another person on your team. In this case, hiring another team member is considered a logical dependency.

Resource dependencies

Resource-based dependencies are project restraints as they relate to the limited amount of resources that you have for your project. If there are additional resources available for the project, this dependency would not be an issue. Effective allocation of resources is key to managing these types of project dependencies.

For example, the progress of Project B is dependent on a single designer finishing Project A so that 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. 

For example, an editor may require one final review before sending an article to publish. While this is a step that's created by the team to ensure there are no mistakes, this step isn't necessarily needed for the project to be completed.

​​External dependencies

External dependencies are tasks that are dependent on outside factors that you or your team have no control over. Internal dependencies are more common, as they rely on things that your team can control.

A good example of an external dependency is when a weather phenomenon prevents a shipment of fresh fruit from arriving at a restaurant. A chef could have had a menu that required oranges, but due to a surprise frost, they're unable to create the dishes necessary. The chef was externally dependent on the orange vendor for creating specific dishes. Identifying external factors allows for contingency plans to be put in place.

Types of task dependencies in project management

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

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

• Finish to Finish (FtF): Task B cannot finish until Task A is also completed. This type of finish dependency is common with tasks that have subtasks within them; if the subtasks are not completed, you cannot complete the parent task. 

• Start to Start (StS): Task B cannot start before Task A starts. These are for tasks that are required to run in parallel with each other. A good example of a start dependency is a timed e-commerce launch. A social media marketer may want to post an announcement for a sale going live, just as a web developer pushes the correct web page to go live. The social media marketer does not start until the web developer starts to ensure that the announcement goes out at the same time.

• Start to Finish (StF): Task B must start for Task A to be completed. This is important for situations that require overlap. An example of this would be coverage on a support line. A representative cannot leave until a different representative comes to relieve them of their duties so that there is always someone available to provide customer support.

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 risk of delays and bottlenecks

• Optimized resource allocation

• Increased chances of completing the project on time and within budget

• Clearer communication and coordination among team members

Personal and team benefits:

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

• Improved team collaboration and productivity

• Opportunity for team members to develop new skills and take on more responsibilities

• Greater sense of accomplishment and job satisfaction 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 optimize task dependencies.

1. Organize tasks using project management software

Finding the right project management tool that works for your team can change the game in terms of internal dependencies. Using a task management tool that can house your project plan, 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 what stage your project is currently in and which tasks are dependent.

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? In the event that one part gets delayed, is the project team prepared for a shift in the schedule?

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. Regular communication is key. 

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.

Keep your task dependencies on track

Want to learn more about how you can better keep track of project dependencies? Learn more with Asana project management resources.

Dependencies FAQ

Which types of dependencies are most common in project schedules?

The types of dependencies most commonly found in project schedules include:

• Finish-to-start (a task cannot start until a previous task is completed)

• Start-to-start (a task cannot start until another task begins)

• Finish-to-finish (a task cannot finish until another task is completed)

• Start-to-finish (a task cannot finish until another task starts).

How do I manage task dependencies?

To manage task dependencies, identify and document the relationships between tasks, communicate dependencies to team members, monitor progress, and adjust the schedule as needed to accommodate any changes or delays.

How do you show dependencies in a project?

Dependencies in a project can be shown using a Gantt chart, network diagram, or dependency matrix, which visually represent the relationships and sequencing of tasks.

What are examples of dependencies?

Examples of dependencies include waiting for client approval before proceeding to the next phase, requiring materials to be delivered before construction can begin, or needing a specific team member to complete their task before another can start.