This executive report provides an overview of the use case scoping within the EMERALDS project, specifically focusing on Task 5.1: Use Cases Orchestration & Validation. The EMERALDS project aims to develop Mobility Analytics as a Service (MAaaS) methods to enhance urban mobility and transportation decision-making. This report outlines the purpose, scope, and objectives of the use cases, emphasizing the coordination, stakeholder engagement, and validation processes involved. The three use cases in the EMERALDS project serve as real-world scenarios to showcase the application of extreme data analytics and Artificial Intelligence (AI) techniques in urban mobility and transportation. The goal is to develop innovative solutions that address complex mobility challenges and contribute to scientific knowledge in the field. The use case scoping document establishes a clear understanding of the research focus, objectives, and challenges associated with urban mobility data. The first use case comprises risk-assessment and forecasting of crowds during events in the beach area of The Hague. The second use case applies traffic network analytics on estimated and predicted multi-modal traffic states to improve traffic management operations in Rotterdam. The third use case aims to investigate public transport network efficiency and passenger trip patterns in Riga by inferring trip characteristics and analysing traffic flows. MAaaS refers to the provision of analytics capabilities and solutions related to mobility and transportation as a service. The EMERALDS project adopts a modular approach, developing distinct components of MAaaS services in various work packages. T5.1 takes a proactive approach in coordinating the use cases, fostering integration, co-creation, and engagement with relevant stakeholders.