Assumptions and Constraints in Project Management

今天，我们将通过查看现实世界的示例来讨论项目假设和约束。

Imagine you want to go shopping at a mall that takes one hour to reach by car.

You assumed that you would leave your home at around 6:00 pm and reach the mall by 7:00 pm.

这是一个假设的一个例子，您认为这是真实的。

What about constraints?

In the shopping example, you can think of two. The first constraint is money. If you have 500 USD in your hand, that’s all you can spend on this shopping trip. The second constraint is the mall’s closing time; let us say it is at 10:30 pm. This means you cannot continue your shopping after that.

Similarly, projects also have assumptions and constraints. You must understand and manage these factors if you want to complete your project successfully.

Let’s dive in.

Project Assumptions and Project Constraints

Project assumptions and constraints are identified at the beginning of the project. Throughout the project life cycle, they will be refined and re-analyzed. Project assumptions and constraints are key to many processes in the PMBOK Guide.

您项目的一个重要方面，假设和约束无法像要求一样管理风险. However, documenting them helps to protect you from future aggravation. You should outline your project’s assumptions and constraints in the project scope statement.

Project Assumptions

一个假设是您认为是真实的。这些是您项目生命周期期间预期的预期事件或情况。您根据自己的经验或手头上可用的信息做出假设。

Assumptions may not end up being true. In fact, they can sometimes be false and may negatively affect your project, adding risk to the project.

For example, let us reconsider the earlier example. You assumed it would take one hour for you to reach the destination. What will happen if you are stuck in traffic and can’t reach the mall on time?

Your assumption turned out to be false. Now your shopping is at risk because you don’t have as much time as planned.

This can also happen to your project.

For example, you assumed that you could get the necessary equipment whenever you needed it. However, you couldn’t get it when the time came due to shortages or supply-chain problems.

Now you are in a difficult situation.

Assumptions play an essential role in developing arisk management plan. Therefore, as a project manager, you must analyze each assumption and predict its impact.

项目假设示例

• You will get all the resources you need.
• During the rainy season, cheap labor will be available.
• All relevantstakeholderswill come to the next meeting.
• 您的团队成员具有所有必要的技能。
• All equipment is in good condition.
• The supplier will deliver consumables on time.

你可以看到,如果any of the assumptions above turn out differently, your project will be radically affected.

Project Constraints

项目的约束limitations imposed on the project, like the budget, schedule, or resources.

The PMBOK Guide识别六个项目限制：范围，质量，时间表，预算，资源和风险。新万博登录手机版在这六个中，范围，时间表和预算被称为三重约束。

These constraints are defined at the beginning of your project, and you must work within their boundaries.

A constraint can be of two types:

1. Business Constraints
2. Technical Constraints

Business Constraints

Business constraints depend on the state of your organization. They are high-level constraints and often defined when the project starts, like time, budget, and resources.

Changes to these constraints are rare, and the project management team has to work within them.

Technical Constraints

技术约束限制您的设计选择。它们是固定的，对技术规格的任何更改都可能影响您的项目计划。

For example, let’s say you’re constructing a pipeline. According to the design, the pipeline should withstand a certain amount of pressure; this is your technical constraint, a fixed reality.

Every project has constraints. Therefore, you must identify all of them and develop your plan accordingly. Constraints are outside of your control, imposed by clients, organizations, or government regulations.

Project Constraints Example

A few examples of constraints are:

• 你必须达到第一个里程碑within one month.
• You have to work with the available resources.
• 您只有两名现场工程师。

假设与约束

The following are a few differences between assumptions and constraints:

• Assumptions are believed to be true, while constraints are true in nature.
• Assumptions are good for the project, while most of the time, constraints are not favorable to the project objective.
• 如果假设成为错误，则对该项目来说是个坏消息。但是，如果约束是错误的，则是积极的。

假设和约束在计划过程中作为项目管理计划的基础起着至关重要的作用。

Any assumption is a potential risk for your project, because, if any assumption is incorrect, you are in trouble. Yourrisk managementplan heavily depends on assumptions and constraints. Failing to identify any of them can affect your project.

概括

Assumptions and constraints are an important part of your project. They need to be identified, controlled, and monitored continuously.

An assumption is a condition you think to be true, and a constraint is a fixed limitation on your project. Assumptions need to be realistically analyzed, while constraints need to be clearly identified throughout the project lifecycle. Managing assumptions and constraints are necessary to complete your project with minimal obstruction.

Project assumptions and project constraints are essential topics from a PMP certification exam point of view. You may see questions about this.

您项目对您的项目的假设和约束又如何呢？请通过评论部分分享您的经验。