With the rapid development of Internet technologies, various paradigms of learning can be adapted to e-learning environments. One of these paradigms, Computer-Supported Collaborative Learning (CSCL), can be presented to learners through web-based systems such as LMS while incorporating peer-to-peer (P2P) learning, measurement, and evaluation strategies. In this book titled Intelligent Data Analysis for e-Learning Enhancing Security and Trustworthiness in Online Learning Systems, various strategies and applications are presented to ensure trustworthiness in e-learning environments, especially where the CSCL paradigm is adopted. A comprehensive literature review on student security, privacy, and trustworthiness has been presented in a very detailed and comprehensive way. This allowed readers to conceptually prepare for detailed applications in the later parts of the book and case studies at the Universitat Oberta de Catalunya. In addition to the applications that are presented in detail, the approaches and techniques such as Learning Analytics, Educational Data Mining, distributed computing, and massive data processing are shared through detailed applications of how to adapt to the measurement and evaluation applications offered in online learning environments in the context of trustworthiness.