Understanding Project Management Dependencies

Project management dependencies play a key role in determining a project’s success. They provide the sequence in which tasks must be performed, which affects the project timelines, resource allocation, and project flow.

So, you must effectively manage the dependencies to ensure tasks are completed logically, prevent bottlenecks, and minimize delays.

In today’s article, I will explain project management dependencies, various types of dependencies and their importance, task-dependency relationships, and strategies for managing them to increase project efficiency.

Understanding and controlling dependencies is essential for you to achieve your project objectives.

Project Management Dependencies

In project management, dependencies are critical relationships between tasks that dictate the execution order.

For example, you cannot start excavating the road to lay the fiber cable without getting the necessary approvals from various government departments.

Dependencies ensure a logical sequence and help build and manage project schedules efficiently. They are the relationships between tasks or activities where one task relies on completing or initiating another task. Understanding and managing these dependencies is key to ensuring the project progresses smoothly and stays on schedule.

Dependencies impact project timelines by determining the sequence of tasks, which can cause delays if one task is obstructed. Efficient resource allocation relies on understanding dependencies to ensure resources are available when needed. Dependencies also influence risk management. If you miss any mandatory dependency or select the wrong sequence of activities, it can cause risks and negatively affect the project.

Effectively managing dependencies ensures a smooth workflow, timely task completion, and optimal resource use, thus reducing the risk of project delays and cost overruns.

Types of Dependencies in Project Management

In project management, dependencies can be of four types:

1. Mandatory Dependencies

These dependencies are often known as “hard logic.” Mandatory dependencies are legally required or inherent, and you cannot ignore them. For example, you cannot lay the ceiling until you construct the walls.

The activity cannot be performed in this dependency until the previous activity is completed.

For example, consider a project to construct a 200-km pipeline from one city to another. This will involve navigating several terrains, such as rail lines, streams/rivers, and motor highways. 

Will you proceed without getting the necessary government approvals? 

You cannot, as you require approval from various government agencies to proceed.

Mandatory dependency can be external or internal.

2. Discretionary Dependencies

This dependency depends on the preference of the project management team and is often known as preferred, preferential, or soft logic.

If a task can be completed in multiple ways, the project team decides on a particular method based on their experience, best practices, or lessons learned.

For example, electrical work must be completed before the painting starts.

Both activities can be performed independently; however, the project team prefers the electrical works first.

Another example is that plumbing work must be completed before electrical works start. 

Discretionary dependency should be decided according to best practices. Factors like convenience, economy, safety, etc., affect the choice of discretionary dependencies. 

3. External Dependencies

External dependencies are external to the project, and the project team has no control over them. These activities are usually non-project, such as relations with the vendor, client, financial department, etc.

For example, you may have a supply agreement with the supplier, and your activity may depend on the materials supplied by the supplier.

Another example is if an OEM (Original Equipment Manufacturer) tells you it will take six months to deliver pipes onsite. 

This dependency is not within your control and is like a schedule constraint.

4. Internal Dependencies

These dependencies are internal to the project management team, and they have complete control over them. The team decides on these dependencies while developing the project management plan.

Internal dependencies can be mandatory or discretionary.

For example, completing the design phase before construction is an internal dependency.

Activity Relationship Dependencies

Many professionals use activity relationships and dependency interchangeably. This is incorrect; although activity relationship and dependency are related, they differ.

Dependencies tell you whether one activity relies on another, but they do not tell you how. It is possible that both activities can start together or one after the other. It is also possible that one activity must be completed before the other activity can start.

This is where the activity relationship comes into the picture. 

Like dependencies, activities can have four types of relationships:

1. Finish-to-Start

Finish-to-start is a logical relationship in which a successor activity cannot start until a predecessor activity has finished.

This is the most-used activity relationship. In this relationship, Activity B cannot start until Activity A is finished. This is where a mandatory dependency comes in.

For example, you cannot start painting before you finish plastering the walls.

2. Finish-to-Finish

Finish-to-finish is a logical relationship in which a successor activity cannot finish until a predecessor activity has finished.

Activity A must be finished simultaneously with Activity B. Although these two activities may not start simultaneously, one cannot be completed until the other is completed.

For example, in event planning, setting up the audio-visual equipment (Task B) cannot be completed until the venue setup (Task A) is finished. Both tasks can proceed in parallel, but the AV setup’s final adjustments depend on the fully arranged venue, illustrating a Finish-to-Finish relationship.

3. Start-to-Start

Start-to-start is a logical relationship in which a successor activity cannot start until a predecessor activity has started.

Activity A must start simultaneously or shortly after Activity B starts.

An example is the conditioning of test equipment and the preparation of results recording tables: they occur simultaneously.

4. Start-to-Finish

Start-to-finish is a logical relationship in which a successor activity cannot finish until a predecessor activity has started.

Activity A must start before we can finish Activity B.

For example, in a hospital shift change, the night shift nurse (Task B) cannot finish their duties until the day shift nurse (Task A) starts their shift. The completion of the night shift depends on the start of the day shift, illustrating a Start-to-Finish relationship.

Another example is when you cannot power off a standby generator until normal power is restored.

How to Manage Dependencies in Project Management

The following guidelines can help you manage project-management dependencies.

Identify and Map Dependencies

During the identify and sequence activity process, ensure you have identified all project activities, found their dependencies, and sequenced them logically. Afterward, you can visually map these activities. Visualizing can help you find more dependencies and ensure the identified dependencies are correct.

You can use a Gantt chart, Kanban board, or project network diagram to identify and map dependencies.

Communicate with Stakeholders

After identifying dependencies and creating the sequence, you must communicate it to stakeholders to gain their understanding and buy-in. They must understand the task dependencies and the consequences of altering them in later stages of the project.

Update the Risk Register

Mandatory dependencies can cause risk. You must identify external and mandatory dependencies and ensure they don’t affect your project objective.

Keep monitoring the assumptions and constraints. While developing the schedule, you might have to consider many assumptions. If these assumptions are false, they can affect your project objectives, so keep watching them.

Develop Contingency and Fallback Plans

Develop contingency and fallback plans to manage risks related to dependencies. Fallback plans are used when contingency plans fail to contain the risk.

Benefits of Managing Project Management Dependencies

A few benefits of efficient dependency management are:

• Better Schedule Development: Dependencies are vital in project planning, as they determine task sequences, resource needs, and risks. Understanding dependencies can help you develop robust scheduling, resource allocation, and risk assessment. By identifying and addressing dependencies early in the planning phase, you can create realistic schedules and avoid delays.
• Improved Coordination: Identifying and managing dependencies ensures that different tasks and teams are coordinated effectively. It prevents delays caused by waiting for a predecessor task to be completed before starting another.
• Optimized Resource Allocation: Understanding dependencies can lead to more efficient resource allocation. By knowing which tasks depend on others, you can prioritize resources accordingly, thus ensuring that critical tasks receive the attention and resources they need.
• Better Stakeholder Management: Managing dependencies will allow you to set realistic expectations for stakeholders regarding project timelines and deliverables. It can also help you communicate delays or changes more effectively, which builds stakeholder trust and confidence.

Conclusion

Dependencies in project management are crucial for ensuring that tasks are completed in a logical, correct order. Identifying, managing, and communicating these dependencies can reduce risks, prevent delays, and increase the chances of project success.

You can optimize resource allocation, improve team collaboration, and ensure timely delivery by leveraging effective tools and strategies to manage dependencies. Understanding and addressing dependencies is vital for managing project complexities and achieving project success.