This work presents a theoretical perspective based on a bibliometric analysis of the research on intellectual capital and environmental sustainability (IC&ES) during the period 1990–2022. Using the Web of Science as the reference database, 291 valid documents were collected and examined through a performance bibliometric analysis and a science mapping analysis based on co-word bibliographic networks, with SciMAT as the analytical tool. This study provides a comprehensive overview of the IC&ES literature from a holistic perspective, enabling the assessment of the increasing scholarly attention to this research topic. Through an in-depth analysis, the specific themes and thematic areas that shape the IC&ES literature are identified, along with their evolution dynamics and interrelationships. The main contribution lies in the identification of four thematic areas—Showing, Inventing, Profiting, and Greening—as well as these cross-fertilizing subdomains that illustrate the main trends and highlight the versatility of the intellectual capital concept and the interdisciplinary nature of the IC&ES field. The findings indicate that the literature on the topic is undergoing a growing specialization, marked by conflicting perspectives from which significant implications can be drawn.