The editorial introduction to Issue 41 of Complex Systems Informatics & Modeling Quarterly focuses on practical applications and methods to manage complex information systems in today's competitive business environment. The issue features articles that provide insights into business process modeling, digital marketing, blockchain technology in accounting, algorithms for detecting users' behavioral models, and text retrieval in restricted domains. These articles offer valuable tools and strategies for researchers and practitioners navigating challenges in managing complex information systems, particularly in Small and Medium Enterprises (SMEs) and public organizations.