How to Write a Good Product Requirements Document (PRD)

A Product Requirements Document (or PRD) is a document containing the customer’s requirements for products or services provided by the contractor. It is the main project document describing software product development.

It can be one page or a whole bundle in volume. Everything depends on the particular features of the project. For example, you can write a Product Requirements Document for a small landing page or complex software featuring machine learning and other tweaks.

As a rule, a product requirements document is drawn up as annexes to the software development contract and is an integral part of it from the moment the parties have signed it.

Who should write the Product Requirements Document?

It is quite a sizeable task that has to be paid separately, the same way design, integration, or coding is paid. A good PRD takes the specifics of the customer’s business processes into account, as well as describes all the necessary and possible options for system behavior. It should also describe user interfaces and their features.

There are several options for solving this problem:

1. The customer writes a PRD, and then, the contractor manager reads it and clarifies all the details. After that, developers read the PRD and make comments/recommendations (if any). Finally, the manager validates an updated PRD version with the customer. This process may require several iterations.
2. The project manager (or business analyst) writes a PRD, validates it with the development team, and after that with the customer. This approach may require several iterations as well.

What we mean is that someone who better understands what the customer wants (the customer or the manager who acts as an intermediary) should write a preliminary PRD. The one who knows how the system can, should, and will work (developer) has to write the final PRD with technical details stipulated.

Why You Need a Product Requirements Document

To make the expectations at the beginning of the project meat the reality after its completion, people came up with the idea to write formalized (written using templates and standards) Product Requirements Documents.

This document solves several important issues:

• allows you to accurately determine the scope of the upcoming work;
• allows you to agree on the procedure to implement them;
• allows estimating the project cost;
• allows planning the deadlines;
• becomes a tool for a project acceptance procedure (everything written in the PRD must be done exactly as stipulated).

In fact, there many more arguments in favor of a PRD than provided in the list above. A maximally detailed PRD will benefit both parties to the contract:

• the contractor, as it will clearly define obligations regarding the features of the product being created, and hence, it will allow avoiding the situation when the customer includes additional requirements not available in the original pre-agreed PRD;
• the customer, accordingly, as it will clearly define the requirements for the product with a view to its subsequent identification.

The Components of a Product Requirements Document

There are a huge number of completely different PRD templates you can use to develop websites, mobile apps, software products, etc. It does not even matter which template you will choose, the main thing is that you will be able to define everything clearly and in simple terms.

As we already mentioned above, everything will depend on the template you choose, but there are basic blocks/sections included in a PRD most often:

• general information about the product planned;
• software purposes, goals, and objectives;
• product requirements (in particular, its functional features, reliability, safety, operating conditions, etc.);
• system usage scenarios when basic business processes are carried out (impose a vision of the solution on real processes, describe at what stages and how it will be used);
• requirements for software and operational documentation;
• stages and phases of product development (what, when, and how it will be done);
• the control and acceptance procedure (how the work will be accepted, what can be considered completed);
• applications (sketches, drafts, and prototypes).

The document may include supplements with various applications with diagrams, tables, calculations, and other similar materials to use them in software development.

What the Customer Risks, Starting a Project without a PRD

Software development teams that adhere to a flexible development methodology (agile, scrum, etc.) use concept documents like sketches, userstories, etc. instead of a clear and rigorous PRD. Using them, they set a direction vector and hammer out details during the development. However, even in this case, such a document should be available at least at a basic level.

Can a project be a success without writing a PRD? Sure, it can. If the project is very simple (1 page on 1 screen with a subscription form and there are no design requirements), or exclusively ready-made solutions are used. In this case, the customer should be ready to agree to developers’ decisions and trust the developers 100%. Such projects are few and most of them are typical.

Besides, it is difficult to adequately assess the project without a PRD. Such an assessment will certainly be of low accuracy. The final budget may exponentially differ from the originally named value.
Having started to work on a project without a PRD, you run a risk to completely fail it. In some cases, it does not even come to development since it is not clear what exactly is to be done.

If you are facing the task of implementing an IT project and have to write a PRD, you can contact us. The Lvivity specialists will answer your questions and advise you on the best ways to do things in your very case.