Needful Things: The Flat Black Sandal

Row 1:  1 // 2 // 3 // 4
Row 2:  1 // 2 // 3 // 4
Row 3:  1 // 2 // 3 // 4
Row 4:  1 // 2 // 3 // 4

It always seems like the simplest things - a white tee shirt, a great pair of jeans - are the hardest to find.  The dilemma I find myself in now is the search for the flat black sandal.  I somehow have no black sandals (other than a dressy pair) in my possession and need something easy for everyday wear.

What I'm looking for is flat or with a small heel (under 1"), comfortable and easy to walk in, casual enough for everyday use, but not so casual that I can't wear it to work (in my very casual office).  I'm not a huge fan of ankle straps, but they are dealt with on a case by case basis.

My frontrunner right now is the Ancient Greek Clio sandals (Row 3, #2), but of course, they're also one of the most expensive pairs.  I've heard their quality is top-notch, so I would likely get a few seasons of wear out of them.  

I'm also partial to the J. Crew Factory pair (Row 2, #4) because they're so basic and the Joie sandals (Row 4, #4) because they're so unlike the others.

Which ones are your favorites?  Anywhere else I should be looking?