Open source software (OSS) is probably the best known exemplar of open innovation, with many practitioner-oriented publications having debated the merits and drawbacks of OSS in recent years. Nevertheless, much of the academic research on OSS has focused on individual rather than organizational issues. Hence while there is some understanding of why individual developers and users opt for particular OSS applications, relatively little is known about the adoption of OSS as a software acquisition policy. This paper presents a study of 13 managers in the secondary software sector in Europe, and examines how their perceptions of the benefits and drawbacks of OSS affected their decision to adopt an open source policy for software in their companies. The study reveals how their perceptions of the business and technical benefits and drawbacks of OSS influenced the technological, organizational, environmental and individual factors considered within the adoption process. The findings reveal that many of these factors are similar to those reported by previous work on the adoption of innovation, leading us to conclude that organizational processes for the adoption of open innovation are reliant on the practices for closed innovation despite frequently cited loss of organizational control associated with open innovation.