Practise = standard? Or guidline?

Context:

Good manufacturing practice

"Good manufacturing practice" or "GMP" is part of a quality system covering the manufacture and testing of pharmaceutical dosage forms or drugs and active pharmaceutical ingredients, diagnostics, foods, pharmaceutical products, and medical devices. GMPs are guidance that outline the aspects of production and testing that can impact the quality of a product. Many countries have legislated that pharmaceutical and medical device companies must follow GMP procedures, and have created their own GMP guidelines that correspond with their legislation, basic concepts of all these guidelines remains more or less similar that is ultimate goal to safeguard the health of the patient, producing a good quality medicine or medical devices or active pharmaceutical products.

More:

http://en.wikipedia.org/wiki/Good_manufacturing_practice