Unstable software requirements are common and call for Agile practices. On the other hand, quality standards and recommendations, to which companies must adhere to play in selected markets, enforce formality in the development process. We present an approach, tailored for a real company, which reconciles these extremes. We used as inputs the original software development process and its formality constraints, the difficulties felt by the company, and various agile approaches. The outcome has been tested in various cases with encouraging results regarding awareness over project progress, requirements management, control of allocated effort and time, and product quality. Although the approach was customized for a specific company, it may be insightful to others facing similar challenges.