In knowledge-intensive services innovative behaviour of co-workers is a critical success factor. In sectors like consultancy, research and architecture the nature of the work implies that projects are never alike. Innovative behaviour means that co-workers generate ideas for better and/or different products, services or working methods, and strive for implementing such changes. By carrying out certain leadership styles, entrepreneurs are able to boost innovative behaviour of their employees. This study presents an overview of innovation-enhancing leadership styles.