This book presents joint works of members of the software engineering and formal methods communities with representatives from industry, with the goal of establishing the foundations for a common understanding of the needs for more flexibility in model-driven engineering. It is based on the Dagstuhl Seminar 19481 „Composing Model-Based Analysis Tools“, which was held November 24 to 29, 2019, at Schloss Dagstuhl, Germany, where current challenges, their background and concepts to address them were discussed.The book is structured in two parts, and organized around five fundamental core...