Developing Design Principles

by July 13, 2009

In my Parti & the Design Sandwich talk, I highlight the role design principles can play in keeping complex, multi-stakeholder projects moving toward a coherent whole. If they can work for Microsoft Windows and Office (two extremely complex and stakeholder-rich products), design principles can work elsewhere as well.

“Design principles are the guiding light for any software application. They define and communicate the key characteristics of the product to a wide variety of stakeholders including clients, colleagues, and team members. Design principles articulate the fundamental goals that all decisions can be measured against and thereby keep the pieces of a project moving toward an integrated whole.”

In order to be most effective, however, design principles need to provide teams with a way to gauge design decisions. That is, they should be specific enough to help groups of people choose between different design options. Unfortunately, many team's first tendency when creating design principles is to go too broad. Principles like "make it easy to use", "keep it fast", or "put the user first" are usually some of the most common ideas that spring to mind.

But it's much more effective to have design principles that account for a product's specific user needs and business goals. As an illustration, consider the difference between Facebook's recently published design principles and those underlying the HTC Sense user interface.

Facebook's design principles:

  • Universal: our design needs to work for everyone, every culture, every language, every device, every stage of life.
  • Human: our voice and visual style stay in the background, behind people’s voices, people’s faces, and people’s expression.
  • Clean: our visual style is clean and understated.
  • Consistent: reduce, reuse, don’t redesign.
  • Useful: meant for repeated daily use
  • Fast: faster experiences are more efficient and feel more effortless.
  • Transparent: we are clear and up front about what’s happening and why.

As you can hopefully see, Facebook's design principles are quite broad but could still help with top-level decisions. "This interface feels too busy." "We already have a design pattern for that, reuse it instead of inventing a new one." Overall, though, these design principles don't seem specific enough to define a unique product experience. After all, just about every Web site out there aspires to be universal, useful, fast, and consistent. Human, clean, and transparent might stand out a bit more as unique to Facebook but even there they feel a lot more like basic principles of good design instead of product-defining statement.

Consider Dieter Ram's ten design commandments:

  • Good design is innovative
  • Good design makes a product useful
  • Good design is aesthetic
  • Good design helps a product to be understood
  • Good design is unobtrusive
  • Good design is honest
  • Good design is thorough to the last detail
  • Good design is concerned with the environment
  • Good design is as little design as possible

Note any similarities?

Contrast this broad approach to defining design principles with HTC Sense's design principles:

  • Make it Mine: personalization needs to reache a level never before possible.
  • Stay Close: staying in touch with the people in your life means managing a variety of communication channels and applications.
  • Discover the Unexpected: many of the most memorable moments in your life are experienced, not explained

The HTC Sense design principles are quite specific and thereby uniquely define the product experience. So much that, the HTC Sense design principles even serve as the primary marketing message around the entire product.

Microsoft's use of design principles is also quite specific. Consider the difference between the principles underlying the redesign of Microsoft Office and Microsoft Windows. For the Windows 7 desktop design, Stephan Hoefnagel showed the following principles in action:

  1. Reduce concepts to increase confidence
  2. Small things matter, good and bad
  3. Solve distractions, not discoverability
  4. Time matters, build for people on the go
  5. Value the full lifecycle of the experience
  6. Be great at “look” and “do”

For the Microsoft Office 2007 redesign, Jensen Harris illustrated how these “design tenants” helped the team make effective decisions:

  1. A person’s focus should be on their content, not on the UI. Help people work without interference.
  2. Reduce the number of choices presented at any given time.
  3. Increase efficiency.
  4. Embrace consistency, but not homogeneity.
  5. Give features a permanent home. Prefer consistent-location UI over “smart” UI.
  6. Straightforward is better than clever.