It's not necessary to put a light on each step, but you'll want to space them in such a way that a general glow is created and no dark spots exist. If they are installed on the tread, they are most commonly located on one side or the other, sometimes alternating along the course of the stairway.

Should I put lights on stairs?

In most cases, lighting on staircases isn't purely a decorative theme, it also serves a very real function in terms of safety. Glare should be avoided and maintenance considered, whilst using interior lighting to enhance the form can add beauty and softness.

How do you illuminate steps?