The global quest for sustainable and efficient energy solutions has led to significant advancements in solar energy technologies. Among these, solar concentrators based on luminescent materials have emerged as a promising area of research, offering a unique combination of efficiency, versatility, and potential for integration into various environments. This review comprehensively analyzes the state-of-the-art luminescent solar concentrators (LSCs), exploring their fundamental principles, recent developments, and prospects. We begin by outlining the basic operating principles of LSCs, including the role of luminescent materials in absorbing sunlight and re-emitting it at longer wavelengths and the subsequent waveguide-based collection of this light to achieve concentration. The review then delves into the various luminescent materials used in LSCs, such as organic dyes, quantum dots, and perovskite nanocrystals, discussing their optical properties, performance metrics, and stability. Much of the review is dedicated to the latest advancements in LSC design, including integrating photonic structures and using spectral conversion layers to enhance light absorption and reduce re-absorption losses. We also explored the integration of LSCs with photovoltaic cells and other renewable energy systems to create hybrid systems with improved energy conversion efficiencies. The challenges facing the widespread adoption of LSCs are critically examined, including issues related to material stability, cost, scalability, and the trade-offs between efficiency and concentration ratios. Strategies for overcoming these challenges, such as developing new materials and optimizing device architectures, are discussed. Finally, the review concludes with an outlook on the future of LSCs, highlighting the potential for these devices to play a significant role in the next generation of solar energy harvesting systems. Integrating LSCs with emerging technologies, such as building-integrated photovoltaics and bright windows, is discussed as a pathway to achieving sustainable and ubiquitous solar energy utilization.