Beverly International
Vyotech
Solar, TwinLab, Solaray
These companies alll practice GMP, which is a better source for information. Which is better is USPS, which is a government pratices for making products. Beverly makes the best protein hands down, it is a medical fact, so no debates there. Solgar, TwinLab, Solary all have GMP. Vyotech, smart products. Cytodyne makes good ZMA, but the rest of the line is crap.