In Sweden, peak-hour travel demand is ranked as the most important operational cost driver for public transport, linked to school and work hours. Achieving a more balanced demand throughout the day is therefore crucial for resource efficiency and promoting environmentally friendly transport. This study aims to gain a deeper understanding of the process of implementing staggered school start times to spread out travel demand, focusing on stakeholder impact and how implementation influences outcomes. In-depth interviews were conducted with key stakeholders from two Swedish cases where staggered school start times were implemented. How the implementation was designed and executed had a considerable impact on its outcome. In the studied cases, the process was led by the school transport actor and the sole objective of reducing operational transport costs was met. However, there were negative impacts on school operations, pupil and teacher scheduling, after-school leisure time, and family planning. These negative effects arose from a lack of stakeholder inclusion, limited knowledge of each other’s operational planning processes, and insufficient leadership across all organisations. This study identifies key contextual factors influencing success or failure, outlines transferable lessons for other regions, and contributes to insights into the distribution of positive and negative effects among stakeholders. Ultimately, staggering start times can reduce transport costs and potentially expand the public transport market, thereby contributing to a more sustainable and efficient transport system. A viable implementation requires allocating ample time and resources to successfully combine the complex planning and operational processes for transport and school.