BPMDS.-  Large and Complex Business Process Modeling and Development.- Towards a knowledge base of business process redesign: Forming the structure.- Coordinating Large Distributed Process Structures.- Early validation framework for critical and complex process-centric systems.- Execution and Understandability of Declarative Process Models.- Logic based Look-ahead for the Execution of Multi-Perspective Declarative Processes.- Exploring the Understandability of a Hybrid Process Design Artifact Based on DCR Graphs.- Novel Approaches in Enterprise Modeling.- A Landscape for Case Models.- Testing the Fractal Enterprise Model in Practice (Experience Report, Short Paper).- Transformative Business Process Modeling, Development, and Support.- Augmented Reality-based Process Modelling for the Internet of Things with HoloFlows (Idea Paper).- The Rise of Enforceable Business Processes from the Ashes of Blockchain-based Smart Contracts (Short Idea Paper).- EMMSAD.- Foundations of modeling and method engineering.- A Continuous Delivery Pipeline for EA Model Evolution.- A Situational Approach to Data-Driven Service Innovation.- On the Need for Intellectual Property Protection in Model-Driven Co-Engineering Processes.- Enterprise, business process and capability modeling.- Dynamic adaptation of capabilities: Exploring meta-model diversity.- A Process for Tailoring Domain-Specific Enterprise Architecture Maturity Models.- Ontology-driven Enterprise Modeling: A Plugin for the Protégé Platform.- Information systems and requirements modeling.- Review-Based User Profiling: A Systematic Mapping Study.- Matching Technology with Enterprise Architecture and Enterprise Architecture Management Tasks Using Task Technology Fit.- A Method for Database Selection.- Domain-specific and  ontology modeling.- Towards Ontological Support for Journalistic Angles.- A system for semi-automatic construction of image processing pipeline for complex problems.- Specification and Management of Methods - A Case for Multi-Level Modelling.- Evaluation of modeling approaches.- The Usage of Constraint Specification Languages: A Controlled Experiment.- Dealing with Structural Differences in Serialized BPMN Models.- Evaluating Usefulness of a Fractal Enterprise Model. Experience Report.

This book constitutes the proceedings of two events held at the CAiSE conference and relating to the areas of enterprise, business process and information systems modeling:The 20th International Conference on Business Process Modeling, Development and Support, BPMDS 2019, and the 24th International Conference on Evaluation and Modeling Methods for Systems Analysis and Development, EMMSAD 2019. The conferences took place in Rome, Italy, in June 2019.The 7 full and 2 short papers accepted for BPMDS were carefully reviewed and selected from a total of 20 submissions; for EMMSAD 15 full papers were accepted from 38 submissions.The papers were organized in topical sections named as follows:BPMDS: large and complex business process modeling and development; execution and understandability of declarative process models; novel approaches in enterprise modeling; transformative business process modeling, development, and support.EMMSAD: foundations of modelingand method engineering; enterprise process and capability modeling; information systems and requirements modeling; domain-specific and ontology modeling; and evaluation of modeling approaches.