Development of new malting barley varieties depends crucially on value chain acceptance. A case study analysis of the adoption of new varieties in malting barley value chains in Canada and the United Kingdom (UK) indicates thatopenness in value chains is a major contributing factor to a faster adoption rate for new varieties, even if firms conduct R&D in-house. Drawing upon the open innovation literature, this paper applies four degrees of openness framework across two dimensions: a firm's level of openness in innovation strategy, and its degree of openness with the rest of the industry