Google Chrome not respecting z-index

Without a link to look at, it's a bit tough to see what the problem might be.

Do you have a z-index: -1; anywhere (a negative number is the key here, doesn't matter the number)? I have found in the past this renders the container void from being interacted with.

Good luck!

I had a weird issue with zIndex on Chrome and I kept fiddling with the position attribute to see if anything worked. But, it didn't. Turns out, in my case, the issue was with the transform attribute. So, if you have a transform attribute in place, disable it and it should be fine. Other browsers work fine with stuff like that, but Chrome seems to play it differently.

Hope this helped you.

Markt's answer (see first answer) is great and this is the "by definition" of the z-index property.
Chrome's specific issue are usually related to the overflow property from the top container bottom. So, for the following:

<div class="first-container">...</div>
<div class="second-container">
    <div ...>
         <div class="fixed-div> some text</div>
    <... /div>
</div>

And styles:

.first-container {
    position:relative;
    z-index: 100;
    width: 100%;
    height: 10%;
}

.second-container {
    position:relative;
    z-index: 1000;
    width: 100%;
    height: 90%;
    overflow: auto;
}

.fixed-div {
    position: fixed;
    z-index: 10000;
    height: 110%;
}

the following actually happens (Chrome only, firefox works as expected)
The 'fixed-div' is behind the 'first-container', even though both 'fixed-div' and its container's ('second-container') z-index value is greater than 'first-container'.

The reason for this is Chrome always enforce boundaries within a container that enforces overflow even though one of its successors might have a fixed position.
I guess you can find a twisted logic for that... I can't - since the only reason for using fixed position is to enable 'on-top-of-everything' behavior.
So bug it is...

Usually when you have set the z-index property, but things aren't working as you might expect, it is related to the position attribute.

In order for z-index to work properly, the element needs to be "positioned". This means that it must have the position attribute set to one of absolute, relative, or fixed.

Note that your element will also be positioned relative to the first ancestor that is positioned if you use position: absolute and top, left, right, bottom, etc.