Charlotte Groeneveld of The Fashion Guitar, NYC, September 2015.
I love Charlotte's style (she is such a lovely person as well) because it is entirely wearable in "real life" as well as during fashion month. Okay, so maybe the gladiator sandals are not practical for running errands with small children in tow on a weekend, but the shirtdress certainly is — just add flat sandals or sneakers. Other white shirtdress inspiration here (on Franzi), here (on Laurel), here (on Leandra — great styling with a choker and fab platform sandals), here, and here on Leigh. 
The white shirtdress = a simple, timeless piece that you can style in so many different ways just by changing shoes and accessories (and perfect for taking on holidays to wear over a bikini).
Recreate Charlotte's look (kind of):
Frame Le Poplin shirt dress, Frank & Eileen Mary cotton-poplin shirtdress, Alexander Wang cotton-poplin shirtdress, J.D.Y. Button-front shirtdress, Acne Studios Button-Front shirtdress, Thakoon lace front shirtdress, Acne Studios Rosamund Pique shirtdress, J.W. Anderson poplin shirtdress, Racil Monaco shirt dress, ASOS shirtdress,  Maud Heline Arozik shirtdress, or Equipment Delaney cotton shirt dress
Gladiator sandals: Francesco Russo buckled leather sandals, Michael Michael Kors Darby gladiator sandals, Stuart Weitzman Gladiator tall sandals, Ancient Greek Thebes lace-up sandals,  Truffle Collection Vela gladiator sandals, Barneys New York Zea wrap sandals, or Marc Fisher Fair gladiator sandals
Fendi Bag Bugs Baguette shoulder bag