Question: I've seen the following bookcases while I was on holiday, and I'd like to make something similar myself. However, I'm puzzled about the structure of the bookcase.

[![enter image description here](https://i.stack.imgur.com/5AcGq.jpg)](https://i.stack.imgur.com/5AcGq.jpg)
[![enter image description here](https://i.stack.imgur.com/7Aa4W.jpg)](https://i.stack.imgur.com/7Aa4W.jpg)

It looks like the vertical side walls are not made out of a single board (as "normally" happens in a bookcase), but are multiple individual pieces, and the shelves are fixed on the top/bottom of the side boards rather than on internal face.

[![enter image description here](https://i.stack.imgur.com/V03I0.jpg)](https://i.stack.imgur.com/V03I0.jpg)

I really like the look of it, but I don't understand how the vertical bits can be fixed safely to the horizontal shelves. Do you reckon there are some metal brackets in the back to keep everything square and to give some structural stability?
How would you fix the shelves to the side boards?

Answer: 
Structurally dubious on the whole, but the back sheet of plywood is probably doing a large part of holding it together, evidently adequately. I do see top brackets to keep it from tipping over.

[![enter image description here](https://i.stack.imgur.com/f3UPy.png)](https://i.stack.imgur.com/f3UPy.png)

I doubt that there's a steel support between each set of shelves, but that would be **a** way to tie it together better, if wanted.

Functionally, it's the all-wooden version of plank and cinderblock (or brick) bookcases. A functional limitation is that the shelves are not adjustable at all, but if you are fine with that, you could certainly replicate this. I would expect that the shelf is drilled and screwed (or nailed) into the support below it, and the hidden side of the support is pocket-screwed (or toe-nailed) into the shelf below it (staggered so they don't conflict) and then the plywood back is attached to the shelf assembly to stiffen it up and unify it.

The bottom-most shelf would presumably be screwed up into the support above, rather than the support being pocket-screwed into it, and the feet are offset so they can be screwed down into from the bottom shelf.

**There may be an additional sctructural detail lurking in the back corners,** mostly hidden by books.

[![detail of leg, exposure enhanced and arrow added](https://i.stack.imgur.com/ltixq.png)](https://i.stack.imgur.com/ltixq.png)

I think this shows the foot/leg board extending up inside the back corner of the shelves, which would provide a good solid hunk of vertical timber to attach all those separate end bits to, and make the structure more solid than I had at first guessed. But it's not showing in the third picture, so it may not extend all that far up. Or the different sets of shelves may be built slightly differently.
The structure looks like a stacking barrister bookcase but without the glass doors. The rear panel is the key to the strength of each unit. Plus add some dowels to keep each unit centered on top of each other.