Wearing a button-down collar shirt with a suit and tie has sometimes been frowned upon by purists.

WSJ: Guide to Men's Shirt Collars: Which Styles Go With Which Occasions and Flatter the Face

Andres Manuel Lopez Obrador strides onto the stage in a white button-down shirt, the collar open, his pose relaxed.

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Brooks Brothers decided to introduce a dressier button-down collar with a higher thread count and made with Italian-woven fabric in its Luxury shirt because sales staff had been getting requests from customers for such a shirt, he says.

WSJ: Guide to Men's Shirt Collars: Which Styles Go With Which Occasions and Flatter the Face