The legal obligation on employers to provide information to employees has grown since the early 1970s. At that time, the emphasis was on disclosure for collective bargaining. In the 1980s and 1990s, the emphasis shifted more to disclosure for joint consultation. In the context of new legislation, the possibility of further interventions from Europe, and a greater commitment to openness in other areas of company and public life, disclosure of information for collective bargaining and joint consultation at work is again on the agenda. This article focuses on disclosure for both of these processes. Disclosure for collective bargaining is the most developed and potentially significant area of the law from an industrial relations perspective. Disclosure for joint consultation, however, has been the most dynamic area in recent years. Voluntary information provision by firms has also been a significant part of developing human resource management practice. The paper therefore provides a broad examination of the law on disclosure. The UK provisions are conceptualised as constituting an agenda-driven disclosure model; i.e. the trigger for their use lies within the bargaining agenda. By contrast, the provisions stemming from European initiatives are event-driven; i.e. they are triggered by specific employer initiated events that affect employment contracts in other ways irrespective of the representative context. In the final sections, we attempt a broader evaluation of the intent and impact of the legislation and assess the pros and cons of the different approaches.