Existing studies on employers' preferences towards institutions of class cooperation suggest that certain types of employers support these institutions because they provide economic benefits. To test this thesis, this paper examines attitudes of German employers towards board-level codetermination. It compares firms' attitudes at the individual and the collective level: individual firms' attitudes are analysed using survey data and media statements from individual executives; collective attitudes are analysed using policy statements from the national business federations. The paper finds considerable support for board-level codetermination among individual firms but continued opposition from the federations. The paper suggests that this difference arises from the federations strategically over-representing dissatisfied members. The promotion of voluntary arrangements allows the federations to campaign against board-level codetermination without alienating the satisfied members. The paper highlights the need to complement a micro-foundational analysis of preference formation with an analysis of intra-associational processes of preference aggregation.