Updated: 11 hours ago
No one can do it all by themselves. We are all dependent on one another as a collective to move forward and progress.
This idea can also be applied to the world of project management. No task exists in isolation: most activities are reliant on another activity’s output in some form; this interaction is called a task dependency.
Here, the term ‘dependency’ refers to the way in which tasks intertwine and become contingent on each other. This article discusses task dependencies in project management and how you can manage them effectively to make sure your things run smoothly.
On the move but still eager to learn more? Watch our video on managing multiple task dependencies here.
Over the course of the guide, we’ll look at:
WHAT ARE DEPENDENCIES IN PROJECT MANAGEMENT?
Dependencies in project management are the relationships between tasks in a project. Understanding how tasks are connected helps to determine the order and timeline in which they should be organized: if task B can’t start before Task A is completed, then it is dependent on task A (which must be scheduled first).
This may all seem relatively simple but as project complexity increases, which is rapidly becoming the norm for those in services delivery (see high-velocity services delivery), tasks are becoming significantly more interdependent on one another. Factoring in all of the different types of dependencies alongside project constraints can quickly become a much trickier challenge to solve.
In large-scale projects, we can end up with an intricate and somewhat mind-boggling web of interrelations between the many tasks involved – and this is where dependency mapping comes in (more on this below).
WHAT ARE PROJECT CONSTRAINTS?
The term ‘project constraints’ refers to the various limitations and risks which you must consider and manage during the project lifecycle. A cost constraint, for example, means you’re hindered by a limited budget, whilst time constraints mean the project must be finished within a specified timeframe.
The majority of project constraints are affected by one another, highlighting the importance of an efficient constraint management strategy. If expanding the project timeline is a must, you will also likely need more funds to complete the project. The scope of your project will also increase when the time and costs do. Poor management here can easily lead to scope creep, especially when project growth becomes uncontrollable.
Taking that into consideration, there are a total of six main project constraints to think about as you progress through each stage of project management. This section details each type in detail and how you can manage them, starting with the big three (known as the ‘triple constraints of project management’) and moving on to consider some additional project constraints.
THE TRIPLE CONSTRAINTS OF PROJECT MANAGEMENT
Also known as the project management triangle, the triple constraints of project management are scope, cost, and time. All of these will need to be balanced in every project, which is never easy because they are all impacted by one another. There are important trade-offs when it comes to balancing these three constraints, and you must always take time to decide the sacrifices you’re willing to make in order to maintain project alignment.
The project scope describes a project’s breadth in respect to quality, detail, and deliverables. Time and money are both constraints that relate closely to the scope of the project: as the project scope grows, so does the need for more time and money to be put in.
You’ll need to be constantly monitoring the ever-growing need for more resources throughout a project lifecycle. This is scope creep and you should take considerable time before and during the project working out how to prevent it wherever possible. The best way to do so is to create comprehensive project plans to ensure all relevant stakeholders have signed off on everything before the project starts.
The main focus of cost constraints is the project budget and any other financial concerns that may affect the project. There are many items that can be cost constraints, including:
Equipment and facilities costs
When we’re talking about cost constraints, you must keep in mind that it’s best to communicate early and frequently. No one, especially directors, like being surprised by a sizable bill. If an unexpected bill emerges, take the time to work out how it will affect the rest of the project, and decide whether it is worth inputting more funds.
A good time management strategy is crucial for project success, but of course there are a number of time constraints you will have to face during each stage of the project. If you attempt to increase your project timeline, issues will arise such as less time for planning, extended deadlines, and unscheduled adjustments to teams’ calendars. Some of these time constraints include:
Hours spent working on project
Overall project timeline
Number of project stages
Time dedicated to planning and strategy
ADDITIONAL PROJECT CONSTRAINTS
Now that you have a better understanding of the triple constraints of project management, there are three more constraints you may come across throughout your project lifecycle. These are quality, resources, and risk.
Project quality measures how successfully your project deliverables have met the expectations set out at the birth of the project. The final project quality is the ultimate result and is therefore impacted by every project constraint. However, project quality still exists as its own constraint as there are many factors that can impact a project’s quality that aren’t directly related to cost or time.
These can be:
Excessive project alterations
Poor development and design
Project quality needs to be managed as an individual entity while ensuring the other five constraints are well balanced to maximize project performance. The cost of poor constraint management can gravely impact the quality of the project and as a result can contribute to low customer satisfaction.
Resources are closely associated with cost constraints because these project requirements will always cost money. A lack of effective resource allocation can result in poor project quality, an unsolicited budget increase, and delays to the project timeline.
Some of the resource constraints you should consider are as follows:
Facilities and infrastructure
Ensure you have a detailed resource management plan in place from the outset to guarantee that you have the resources necessary for every stage of the project.
Project risks describe any kind of unexpected event that can affect the project. Project risks are commonly associated with negative impacts, but some can be positive. For example, a new software solution may be released during the progress of your project. This new system may help you to finish the project quicker or save costs. Alternatively, it could result in more competition in the market you operate in and therefore reduce your product value.
Risk analysis can be a helpful tool to determine exactly the potential challenges you could face. This, in turn, paves the way for you to put together a good risk management strategy to keep them at the door. Some potential risk constraints include:
Thinly spread resources
Not enough clarity
DEPENDENCY TYPES IN PROJECT MANAGEMENT
Task dependencies are not always the same type, and varying factors both internally and externally can affect them. The following are the main classifications of dependencies that you should be aware of.
These are an integral part of most projects and as such it's tricky (sometimes impossible) to avoid them. Tasks that fall under the logical dependencies category typically use the output of the prior task as input, so they can’t be run simultaneously.
Consider driving a car. You can’t start the car and the process of driving until it is filled with gas.
Resource dependencies are born out of a project constraint – they often arise from concerns about shared resources and how readily available they are to all parties. In a situation where two tasks need the same resource for completion (and this resource can’t be shared by two teams at the same time), each task will be dependent on the other one being completed.
Wherever resource dependencies like this can be anticipated, it is vital to plan the sequence of tasks and be absolutely clear on when one should be finalized so that the other can begin.
Preferential dependencies will often be dependent on the team and its members, as well as various other stakeholders. These will occur when tasks are set to follow standard practices. Typically, you can complete the project even ignoring these dependencies in your tasks, but the quality may suffer.
There will always be things you are unable to control, despite how much planning goes into a project. Some tasks are unfortunately dependent on external factors and project managers can sometimes be unable to influence their progress. The only real way to deal with these is to have a solid backup plan.
Supplier delays are a good example of such dependencies, and the best project managers will no doubt have some sort of contingency plan to ensure everything runs smoothly and as 'on-schedule' as possible in any eventuality.
More commonly associated with larger companies, cross-team dependencies occur when several groups work on a single project and must rely on other teams to complete their respective tasks on schedule. We’re all only human though. Sometimes mistakes happen or unexpected, unavoidable roadblocks arise, which can delay a task at the expense of other teams. An efficient project time management strategy coupled with a good deal of pre-planning between the relevant groups can help to mitigate this.
UNDERSTANDING TASK DEPENDENCY RELATIONS
A crucial part of a project manager’s job is to understand and identify the relationship between different task dependencies. This section details the relationships between the four differing types of task dependencies in project management.
Finish to Start: Task B can only be started when Task A has finished
Finish to Finish: Task A can only finish when Task B ends.
Start to Start: Task B cannot be started before Task A starts.
Start to Finish: Task B must be started for Task A to be complete.
Finish to Start (FS) Dependencies
Finish-to-Start (FS) describes dependencies that can’t start until the prior task is completed (i.e. task A must be finished for task B to start). This is the most frequently occurring type of dependency in projects but don't let familiarity make you fail to recognize which types of tasks fall under this bracket. In the context of software development, for example, there will often be situations in which the back-end developers must finish a certain task before the front-end developers can begin their work.
Finish to Finish (FF) Dependencies
Finish-to-Finish (FF) means that a task can only be completed after another task has been completed. With this dependency, two tasks may run parallel to one another – although activity A must be 100% done for activity B to finish, both activities could be started at the same time without waiting on each other. FF dependencies occur in any scenario where the final output from one task is required for the last stage of another task.
Start to Start (SS) Dependencies
Start-to-Start (SS) dependency is a much less common type of task dependency, so you may not be as familiar with it and how to spot one. An SS dependency signifies when an activity cannot begin before another activity has also started. However, they are not required to start at the same time, nor will they necessarily finish simultaneously – but the start of one task is a necessary precursor to the other. These dependencies are commonly seen in projects which require milestones to be reached on different tasks by certain deadlines (or where the initial deliverable from one task is needed to initiate the next).
Start to Finish (SF) Dependencies
A Start-to-Finish (SF) dependency is one where you can only complete the previous task if the succeeding task has already started. This type of dependency is one of the least common in real-life scenarios, and is usually found in scheduling-related events which include some sort of handover between two tasks. In some rare cases there may be an initial output from task B that is required for the final part of task A.
UPSTREAM VS. DOWNSTREAM DEPENDENCIES
Dependencies can be upstream or downstream, and these terms are often used when describing other projects.
An upstream dependency is when one task must be finished before you can begin another task. You must often wait for a particular activity to be completed before starting work on a different task (or a different part of the same phase of work). For example, Team A’s job to decorate an office has an upstream dependency on Team B’s task to complete the setup of the basic infrastructure.
On the other hand, a downstream dependency is when your team must deliver something before something further down the chain is able to start (i.e. someone is waiting for you to complete a task before they can start work on their own). For example, if team A’s task is to lay the groundwork and foundations for a building and team B’s role is to start constructing the walls, then task A has a downstream dependency on task B.
Wherever a downstream dependency exists in a project, there will always be an equal and opposite upstream dependency: if task A has a downstream dependency on task B, then we can also say that task B has an upstream dependency on task A.
MANAGING PROJECT DEPENDENCIES
Like various other challenges in project management, there is no ‘correct’ way of managing dependencies. The way you deal with them depends on the project specification and requirements. There are however some best practices that all project managers can follow to be more successful when dealing with dependencies between tasks.
Listing Tasks, Assigning Responsibilities, and Labelling Dependencies
One of the crucial steps to making a good project plan is to identify and record every task, clarify the dependencies that are involved and understand the direction in which each task’s dependencies flow (whether upstream or downstream). By not doing this you run the risk of complicating things. Poor planning inevitably limits the possibility of your project being successful.
It's crucial to then assign the tasks you’ve identified to an owner in order to have one main point of contact for each responsibility. The individual responsible for each task should be made aware of all of the up- and downstream dependencies on other tasks, as well as the deadlines associated with these dependencies. To ensure every task can be completed as efficiently as possible, owners should be picked for tasks based on their skill set and organizational skills, so these can be put to use throughout the task.
Identifying Project Constraints and Keeping a Risk Log
In addition to task dependencies, a better understanding of constraints is crucial to mitigate risks in project management. Consider how each constraint and possibility could affect the overall progress of the project if it were to materialize. And bear in mind that projects are often susceptible to external constraints which you have little control over.
A lot of constraints carry significant risks so you need to be prepared for them. Once all have been identified, make clear action plans regarding the most appropriate response to each constraint.
Visualizing the Project With a Dependency Map
Visualizing dependencies is a key component of ensuring great project management. Teams must understand where dependencies exist in order for them to manage them effectively. This can help to limit bottlenecks and avoid any issues that are brought about by poor management.
Dependency mapping is crucial for understanding two things: where dependencies and patterns exist, and how work can be split amongst multiple teams. With no strategy for visualizing dependencies, you risk severe operational mishaps, communication problems, and much more.
ASSIGNING PROJECT DEPENDENCIES IN RESOURCE MANAGEMENT SOFTWARE
Whether you’re an experienced project manager or not, you will need software tools to help complete the job. Precursive makes project management simple and intuitive so you can pick it up no matter what experience you have. Our cloud-based, Salesforce-native project management software includes integrated features like task management and tracking in real-time to help you tackle all of the challenges project managers face.
In Precursive, you can set up task dependencies and assign a predecessor to each of your tasks to create a defined sequence and timeline for your work. You also have the luxury of building multiple task dependencies, meaning you can link multiple successors and predecessors to a single task. This means tasks do not have to be scheduled one after the other, and instead can be run simultaneously by assigning multiple tasks to the same predecessor. You can use our Plan View setting to easily visualize, review, and manage your task dependencies. Whether you’re on-site or working remotely, you can always keep on top of things with Precursive across any device.
Hopefully you now have a better understanding of task dependencies, the different types, and how they interact with one another. Still want to learn more? Have a look at some of our other related resources:
Our cloud-based professional services automation software enables you to schedule tasks and assign dependencies efficiently and effectively, all within the Salesforce platform. Book a demo today to see how we can help you manage your task dependencies and time better.