The primary objective of this article is to assist organisational management to evaluate policies on disclosure of information to trade unions. Such policies form part of the industrial relations system of an organisation, which embraces all aspects of personnel and labour management. I shall be drawing particular attention below to the need to consider the dynamic and interactive effects of information on the components of this system. Before looking directly at issues relating specifically to trade union negotiators, therefore, I want briefly to consider some aspects of communication of information to employees in general since there is clearly a potential interaction with the information supply to union negotiators.