The study focuses on the separation of two classical institutions of collective labour law: the labour unions and the works councils. Traditionally, labour unions are associations intended to represent and protect the collective interests of workers; works councils are units that exercise the workers’ participation rights, and are mechanisms where the employees can influence the decisions of the employer at the workplace. The distribution of traditional union and works council authorities, however, is not that obvious, especially from a practical point of view. The study strives to highlight those areas where the unions and the works councils appear as opposing parties, especially focusing on works agreements with normative power, from a practical and an international comparative perspective, and to offer solutions de lege ferenda.