Since several years there is a trend of reorganizing the process of software development, by applying agile practices like scrum. These practices attempt to increase customer responsiveness and adaptability of the organization. In a longitudinal case study, I discuss the impact of commonly applied scrum practices on team interaction quality. I collected data in a software development project at three different times during the project. The findings indicate the potential longitudinal impact of scrum practices on team interaction quality and performance. First, the results indicate that daily meetings cannot fully compensate the benefits of colocation, which improves the information flow in a team. Second, the quality of the requirements development approach correlates with the degree of requirements fuzziness. Third, staff turnover does not necessarily impact team performance negatively. Fourth, scrum practices can even benefit in a highly regulated environment, in which agility is not an objective.