Marine systems face a multitude of anthropogenic stressors such as climate change, recreational and commercial fishing, aquaculture practices, pollution, and coastal urbanization. These stressors exert escalating pressure on marine ecosystems, leading to noticeable changes in habitat conditions as well as alterations in the abundance and diversity of their communities. Understanding the impacts of these stressors proves challenging due to their interactions with various factors, such as species richness, environmental fluctuations, system openness, stressor tolerance, and the occurrence rate and intensity of each stressor. Therefore, a comprehensive analysis of the entire ecosystem is crucial. It is essential to consider the unique characteristics of each marine environment when assessing the cumulative stress that affects them. This book provides insights into the functioning of marine ecosystems and their responses to both natural and human-induced drivers within the framework of sustainable marine resource utilization. We are confident that this book will make a valuable contribution to the scientific community, serving as a resource to inform decision-makers and the general public about the current state of knowledge regarding the marine environment and the human footprints on our seas.