Digital Arts recently had a chance to talk to site usability expert and consultant Steve Krug about best practices and major mistakes in Web design. Here is an edited transcript of the chat with Krug, who runs a one-man consulting firm called Advanced Common Sense in Boston, has a Web site called Sensible.com and wrote a book titled Don't Make Me Think! A Common Sense Approach to Web Usability.

DA: What are some major Web site usability best practices?

Krug: The main one is to make sure you've done some user testing. Bring people in and have them use the thing while you watch. That's the best practice. Do that throughout the design cycle. Start doing it early. Don't wait until you have a finished new design.

As a designer you know too much about the site. You have to bring in people who don't know anything about the site and have them try and use it. That's my single best practice.

DA: How is user-generated content affecting design and usability decisions? What's the right way to incorporate those features into your design?

Krug: It has become one of those things which everyone now feels compelled [to include on their sites]. You can imagine the conversations in boardrooms with bosses saying: "We've got to have social networking on our site." Because it's worked well for some people, there's a rush for everyone to incorporate it, and that's usually not a good thing. You don't want to have an attitude of "we've got to have it whether or not it makes sense for our organization."

I don't think there are as many usability issues as there are tactical or strategic decisions related to whether incorporating social networking into your site is going to help or hurt. The usability and design issues aren't nearly as important as the issues of whether it's appropriate for the organization and whether you're going to be willing to put the resources into it to manage it. It takes an awful lot of work.

DA: Video has become very popular in the past year. How does it affect design decisions?

Krug: For years, very often the reaction you'd get whenever people would open up a page that had video, was: "Oh, it's interesting but I wouldn't use it because that stuff never works for me." The general reactions were that the video was either not going to load, or be painfully slow to load or would require a plug-in users didn't have. YouTube changed that, because it just works. It plays the video right away, it's not jerky or start-and-stop, and that turned people around. It's not that people suddenly realized they wanted to spend time watching short videos. It was like Amazon, which succeeded because it worked, and Google as well. So if you're going to implement video, do it as well as YouTube does it or don't do it at all.

DA: Are corporate sites today doing a good job of making their sites usable?

Krug: They are certainly doing a much better job than they were five years ago. You can still go to almost any site and find one or two major problems off the bat. But that's the nature of the game with design: There's always going to be issues.

When you go to a site, you usually run into usability problems pretty quickly. They're not hidden. They're not complicated. They're not baffling. They were in the design or crept into the design. That's why I go around advocating that companies do user testing. If you do that, you dramatically increase your chances of getting rid of all the serious problems in the site.

DA: What are some persistent, common problems you run into time and again?

Krug: One I harp on a lot is this bashfulness about telling people what the site is on the home page. When you open a site and go to the home page, you should be able to tell right away who is publishing this, what's it for and what kind of content is here. The entity has to identify itself. ... A tagline or some kind of identifier up in the header space that travels on every page is useful from that regard.

The assumption organizations make is that everyone knows who they are and they don't need to tell them. If you can't fit it in the header [on every page] you want to have a little blurb near the top of the home page at the beginning of the content space. People say: "We don't need to do that on the home page because most people now get here through a Google search and they don't pass through the home page." But the truth is that after people get to a page from a Google search, the next thing they do is go to that site's home page to figure out what this site is.

DA: Should you set an ROI [return on investment] goal for a site usability redesign?

Krug: I find that difficult because it tends to be hard to calculate. Clearly, people proposing the redesign should have specific objectives for what they think will improve as a result of it. They should be able to make some kind of convincing case that this is going to produce some kind of result that will be worth the effort. It's not that hard to come up with. After a site has been up for a couple of years, everyone has a pretty good idea of what's not working.

The trick is to keep the redesign project focused on fixing the things that aren't working, and not just to make the site look better and have a fresh look. There is a significant cost associated not only with the effort of doing the redesign, but you can also have a certain amount of pushback from people who by human nature don't want anything changed.

So I don't know about setting an ROI target upfront, but I do know it's important how you introduce the redesign. You can't just spring it on people. You want to give your existing users a preview of what's going to happen, put up a link saying we're doing a redesign and let them click through some pages of the new design before it's launched.

If people feel you are looking for their input instead of springing it on them, that soothes a lot of people's feelings. And by doing this, you can also get some valid points from people about why they don't like some things. By getting that feedback before you launch it, you can go in and tweak some things and avoid inadvertently ruining the way people were doing things.