Sharing this because most of you are probably trying to hire designers. any other questions I could answer on this topic?

This is key for any hire:

When hiring all that really matters are the big questions: can you work with them, can they do their job and can they help you succeed?

And to further that point, I agree that communication and chemistry are key.

Are there any specific things to look for in an interaction designer, as compared with a graphic artist?

It's so much easier to react to art than to interaction design.

If at all possible use the products they designed. Do you search for buttons? Does it feel good to complete tasks?

When looking at documentation, did they actually do a use case or flow (sketches in notebooks are ok) or did they go straight to wireframes?

What is their favorite website and why?

And the classic "only interview question worth asking" (I wish I could recall who said this) "How would they improve your website, and why?

This tells you first the important question of do they care enough to do their homework.

Then it tells you how they think about problems.

Then you might tell them something they didn't know about the problem, and you can see if they fight, or adjust their change to incorporate the feedback.

Finally I LOVE design exercises. at yahoo (circa 2001) we had a great one where we made people do a quick sketch of a people directory. We got to see if they considered large datasets, different retrieval styles and privacy issues.

I'd recommend having them do a 20 minute sketch of a feature you are considering. here how you run it

Write up a rough half-page spec of the idea. Leave them alone in a room for 20-30 minutes with a whiteboard and many colored markers, or a pile of printer paper and many colored markers. Post-its if you feel generous.

Then bring in everyone who they'll interview at the same time and have the designer explain what they did and why.

Remember they only had 20 minutes, and it doesn't have to be a good solution. But you'll see how they think, and you can image if it'd be fun to work with them.

some designers hate these exercises and will flatly refuse to do them. That will tell you something also. In 20 minutes, it's not free work, it's just getting an insight into how they think, like exercises engineers have to do to show if they can think through a problem.

Since we all have to do design, this seems like a good question for any candidate, not just the designers:

How would you improve this product, and why?

Thanks! .. looking for a designer at the moment.. and while I know what I want and what I like- I dont know how to find that person!