It is not surprising that agile methods are tailored or customized in various contexts and projects. However, there is little advice for practitioners for how to go about tailoring agile methods in large-scale projects. Henceforth, the aim of this experience report is to highlight some of the challenges with large-scale agile software development and especially how to deal with these challenges involves continuous tailoring of the agile method in use. In so doing, we report from a large-scale agile software development effort involving more than 120 participants in a Governmental organization and running for 3,5 years. The project consisted of three deliverables, partly developed in parallel after a delivery model based on Scrum. After a much troubled start related to scaling challenges and architecture complexity during the first deliverable, the project was turnaround and the second and third deliverables were portrayed fairly successful by both supplier and customer. From a practitioner’s perspective, we found that novel practices emerged through out the project that improved the way of working – especially across teams and stakeholders. Based on this, we describe some guidelines for tailoring agile in the large.