How to place svg shapes in a circle?

I'm playing a bit with D3.js and I got most things working. But I want to place my svg shapes in a circle. So I will show the difference in data with color and text. I know how to draw circles and pie charts, but I want to basically have a circle of same size circles. And not have them overlap, the order is irrelevant. I don't know where to start, to find out the x & y for each circle.