5 Tips for Writing Good Design Principles

Strong design principles will help you make better design decisions about products and features

Illustration: Jennifer Hom

Every product or feature should be based on a set of design principles. I’m not talking about universal design principles like “less is more” or “simple.” Instead, I’m talking about design principles that uniquely apply to the specific product or feature that you’re building.

Think of it this way: Universal design principles apply to everything. They’re like air or gravity or other things inevitable and necessary. Just learn then, apply them, and move on. On the other hand, the kind of design principles this article focuses on are those specific to the product or feature you are designing now. Which is different from the other product or feature you designed last month. For example, at Slack we expect the principles that guide design from the Messaging team to be different from principles that guide design from the Search team.

Now, a word on why principles are important. Fundamentally, design principles are important because they help your team make decisions. Design principles should be foundational; set them up first, before you start designing. Then, as you move through the design process, refer back to the principles. Question whether your design decisions uphold the principles or break them. For example, in a recent project related to the redesign of Slack’s information architecture, we established a principle to provide the lowest number of access points possible to meet the user’s primary intent. By sticking with this principle we were presented with the hard work of identifying why people primarily use Slack (with such an open-ended product, there is no shortage of opinions about that) and made hard decisions to eliminate a number of top-level UI elements. But the principle served its purpose. It helped us make decisions, efficiently, and move forward.

One last note before we get to the tips: Design principles are meant to be reflexive. Through the design process you may find that, based on your design and what you learn about it, the original principles may need to be adjusted. Perhaps you receive overwhelmingly positive user feedback on a design that is in conflict with a principle. That’s an indication the…