The following pharmaceutical companies have endorsed the GPP guidelines:

The following contract research and communications companies have agreed to recommend GPP to their clients and to follow GPP in their work: 

The following journals ask authors of industry-sponsored studies, or of papers in industry-sponsored supplements, to follow GPP:

Employees of the following companies contributed to the development of the GPP document at various stages:

The GPP Guidelines have been endorsed by the European Medical
Writers Association (EMWA)