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Sock maker near Braga, Portugal, producing about 3.5 million pairs a year in organic cotton and merino for department stores, chains and brands such as Asket.

Swiss shirting-fabric maker using extra-long-staple Supima and Sea Island cotton, plus cashmere and linen blends, woven at partner mills.

Arequipa knitwear and apparel maker producing alpaca and organic cotton sweaters, coats and accessories for brands and designers; also runs its own label, Anntarah.

Mount Airy, North Carolina wool sock mill that knits merino socks for private-label clients such as REI and L.L.Bean, makes licensed lines, and owns Farm to Feet; some programs use synthetic yarns.