How to write and manage a product requirements document (PRD)
Last updated: November 2024
A product requirements document (PRD) outlines the key elements of a product — helping your development team understand the purpose and functionality behind a build.
A PRD is the single most important artifact a product manager can maintain. This statement was true — assuming you were working in software 25 years ago.
Fast forward to the early aughts, and quite a few product folks were making bold claims about the obsolescence of PRDs. They were relics of waterfall development. Fast-moving agile teams did not want to be bogged down by creating (and updating, then updating again) lengthy PRDs. And almost every product manager today considers PRDs to be passé.
But at its core, a PRD simply contains all the requirements for a product so the product development team can understand what that product should do. When you think about it that way, PRDs are not only still relevant — they are essential. (Even if the format has shifted over time.) New formats for PRDs are available in Aha! software, either on a note template or built right into the work items on your roadmap.
Jump ahead to any section in this guide to learn more:
Try the PRD template below — with a free trial.
Where do product requirements documents come from?
Waterfall. If there is one word that could make any product development team shudder, this would be it. Waterfall dominated as the prevailing methodology from the 1970s up until the 2000s. Teams worked in rigid sequential phrases, each one completed before the next could begin.
PRDs were essential in waterfall, largely because building scalable software products was expensive and time-intensive. Development required a strict plan that accounted for costs and schedules, all vetted through upfront research, feasibility studies, and historical data. There was no room for ambiguity, inconsistency, or missing information. As a result, PRDs — which captured every aspect of the product in precise detail — became indispensable.
PRD limitations within an agile setting
As agile software development took hold, many people found that PRDs were fundamentally at odds with the emerging methodology. Consider the four core values written in the original Agile Manifesto:
Individuals and interactions over processes and tools
Working software over comprehensive documentation
Customer collaboration over contract negotiation
Responding to change over following a plan
The tension is clear. How can a team innovate, iterate, and respond to real user feedback when folks are anchored by extensive documentation detailing exactly what must be built? As technology advanced and made it possible to quickly develop new functionality, nobody wanted to wait for an updated PRD to start building the next enhancement.
Critics argued that creating a PRD slowed progress and limited big-picture thinking. With much of the content in a PRD coming from past market research and historical data, many found these documents backward-looking rather than focused on future possibilities.
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What does a product requirements document look like?
A PRD looks like a table of contents for a product. (Our PRD template serves as a great example.) A PRD should contain the following, usually organized in a series of tables:
Overview: The basics of what you are building, including status, team members, and release date
Objective: Strategic alignment, including organizational goals or initiatives
Context: Customer personas, use cases, the competitive landscape, and other supporting material that will help the team develop a deeper understanding
Assumptions: Anything that might impact product development positively or negatively (along with how you will validate this), and any known dependencies
Scope: What is a current priority and what will not be included now, but might go in a future release
Requirements: Details of what should be built, such as user stories or wireframes
Performance: Success metrics
Open questions: Anything the team anticipates or is currently unsure of how to answer
The example below is a version of a PRD built in Aha! Roadmaps.
What is the difference between a PRD and a feature description?
A PRD and a feature description serve different purposes. A PRD defines more: overview, goals, and functionality. It is a comprehensive blueprint detailing how the product should work, who it is for, and what problem it aims to solve. (Traditional ones can be upward of 30 pages long.)
A feature description focuses on a specific aspect of the product. It describes a single feature's purpose, user interaction, and technical requirements. Whereas a PRD gives you the full picture, a feature description zooms in on one thing. It helps the team understand the details.
How detailed should a PRD be?
The level of detail in a PRD depends on factors such as your product's complexity, your team's experience, and the specific needs of your chosen product development process.
In the past, PRDs were exhaustive documents packed with every possible requirement. Today's PRDs should still cover essential aspects (such as objectives, target users, and core functionality), but without overloading the document with details that could limit adaptability. The goal is to give the team a clear understanding of what to build, all while allowing room for adjustments based on new insights and feedback.
When do you need a product requirements document?
A PRD provides clear, comprehensive documentation that guides development and supports alignment across teams. This is especially true for industries or projects where security, compliance, or complex stakeholder needs demand specific, consistent information.
Industry examples of PRD use
You will often see PRDs in highly regulated enterprise software environments. In sectors like healthcare and finance, for example, functional groups outside the core product team (think: legal and compliance) might need detailed insights into product functionality to complete their work. Legal teams, for instance, might not have direct access to product managers and can rely on the PRD instead. Depending on the product, customer support teams might also rely on a detailed PRD to answer questions.
PRDs are common at software development agencies that build technology for other companies, too. Clear documentation helps ensure that client expectations are met and project scope is understood. These PRDs typically include high-level goals, edge cases, security concerns, and guidelines surrounding client validation and testing.
What are some alternatives to product requirements documents?
Many team members are involved in building, launching, and promoting a product. Some level of documentation and speccing out of what the team will create is necessary, whatever you want to call it.
The product development team needs answers to the following questions:
What is the core objective?
Who are we building for?
What is the true value of what we are building?
How will our users interact with it?
What will it look like?
How will we ensure success upon launch?
The exercise of asking and answering can be useful to help product and engineering managers understand goals, details about the user experience, and the scope of a particular effort. You can move ahead faster when everyone shares the same information.
There are some good checklists that teams can use to define features. Beyond that, here are a few more lightweight alternatives to a PRD:
Jobs-to-be-done framework: Defines what users need to accomplish with the product
Prototypes: Early models that help teams test and refine features' functionality
User stories: Describe features from the user's perspective, including what they need and why
User story mapping: A visual layout of all your different user stories to map the entire product journey
Wireframes and mockups: Visual representations of the product layout and design, used to define the structure and interface elements before moving into development
This is a user story map template in Aha! Whiteboards. Use it to visualize your product based on customer needs.
When should you use a PRD vs. a user story or wireframe?
A PRD is useful for high-level planning and aligning everyone on the product's overall direction. For more tactical work, such as detailing a specific feature or user interaction, user stories or wireframes can be more efficient.
But this is not an either/or scenario. Many product managers combine a PRD with lighter tools to tailor information to different audiences. Imagine a product manager is introducing a new feature for a mobile app. They might start by creating a PRD that builds broad understanding around high-level goals, functionality, and customer outcomes. From there, more targeted tools could help guide specific teams:
The development team might benefit from user stories that break down the feature into actionable tasks from the user's perspective.
Product designers might rely on wireframes to quickly visualize the layout and user flows without needing to reference the full PRD.
And for marketing teammates, a jobs-to-be-done framework could demonstrate how the feature fulfills a specific user need, helping them communicate the value boldly.
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When everyone on the product team understands user problems deeply, you can deliver meaningful customer experiences. The real challenge is helping the team see how the product or specific features solves actual pain points. Call it a PRD or anything else you want — great product managers provide the team with insights that go beyond functionality and get to the core of what customers truly need.
