The trick is to stare at her feet. Stare at the foot she's standing on until she switches.

Thanks guys, but nope. She only goes counterclockwise for me.

If there's anyone out there who thinks it's some kind of trick and that at some point, it flips direction in the animation, you are wrong.

There are exactly 34 frames, which comprise one full rotation. It only changes direction in your mind.

She turns both ways for me.

Counter-clockwise and I can't seem to get her to go the other way around.

Oh well.

I've uploaded a version of the file with the frame order reversed.

Check it out here.

Holy shit!

Just been staring at it for ages, and then suddenly i managed to see it go the other way. Now I can do it as and when!

Amazing!

When I first came to take a look i saw the dancer go clockwise then when I read the spoiler it suddenly changed counter-clockwise! When i look at the dancer I see her go clockwise and/or clockwise when I want ^_^

Mind. Blown.

I've seen this illusion before, and was frustrated. For a long time, I could only get this to go one way. I thought people who could see this both ways were just insane or making it up.

Then Bezou came along and posted the frames in reverse order. At first, I couldn't tell it had been reversed - it looked the same. Then I paid attention to the feet and it suddenly switched on me.

Thanks to Bezou, I "get" this now!

Glad I could help, ]{. I remember seeing this years ago and being convinced it was fraudulent. So I took it apart piece by piece and reassembled it, making sure that there were only the 34 frames. And it still worked.

Our brains are interesting.
Interestingly enough, most people see it spin clockwise, but if you go by frame by frame, it looks to be spinning counter-clockwise.

I saw her going counter-clockwise...then I switched it and she's going clockwise but I can't get her to go back the other way!!!! >.<

This will make changing the direction of the girl so easy.

Kool

If I don't focus on any I can see all three going in the same way.

Same...

I got her to change direction, just stared for like 10 seconds and it changed. Didn't really look at anything particular though.

In a circle.

at first i saw counterclockwise, now i see clockwise and cant see counterclockwise.

but REGARDLESS, she has some perky nipples.

My head exploded and my brains splattered both clockwise and counter clockwise.