In this article, we discuss the impact of software developer motivation on projects. Motivation has been reported to be an important determinant of productivity and quality of work in many industries. In this article, we explore specifically how motivation impacts on development work in software engineering. We describe work previously done to suggest that software developers may have a different profile of motivators to other professionals. We present data collected from nine developers working in a software organisation that has been assessed at CMM level 5. We find that the developers working in this high maturity development environment are highly motivated. We also report relationships between motivation and progress in development work and describe the impact of motivating factors on specific aspects of software development. Our main conclusion is that good software developers are proactive, flexible and adaptable, prepared to share knowledge with team and follow good practice, for example, documenting work. Also, and in particular reference to this high maturity company, good software developers are able to resolve complex problems, innovative and eager to try new technology. The biggest motivators to such performance in a high maturity organisation are pay and benefits, recognition and opportunities for achievement. These are closely followed by technically challenging work, job security and senior management support. Cost, time, product quality — in terms of reliability — and user satisfaction are all moderately good indicators of project success. User satisfaction, however, is the best indicator of all four as its importance assumes a temporal significance as a project progresses. Finally, we found that technical competency, interpersonal skills and adherence to good practices impact favourably on software project success. Copyright © 2006 John Wiley & Sons, Ltd.