Executive functions (EFs) are higher-order cognitive control processes that enable goal-directed behavior, self-regulation, and adaptive functioning across the lifespan. A widely adopted theoretical framework conceptualizes core executive functions as inhibitory control, updating of working memory representations, and cognitive flexibility, rather than treating working memory as an executive function per se. Despite extensive research, the accurate assessment of executive functions remains a major challenge due to their multidimensional and context-dependent nature. This narrative review, informed by systematic search principles, synthesizes peer-reviewed literature published between 2000 and 2024 on executive function assessment. Searches were conducted in Scopus, PubMed, JSTOR, Web of Science, Google Scholar, and HEAL-Link. A total of 85 sources were screened, with 12 representative empirical studies and reviews selected for synthesis. Four major assessment approaches were identified: performance-based tests, computerized assessments, rating scales, and neuroimaging techniques. Each approach offers unique strengths, but also significant limitations related to ecological validity, subjectivity, accessibility, and cost. No single method adequately captures the complexity of executive functioning. The review argues for a multimethod assessment framework integrating behavioral, subjective, and neurobiological measures, and highlights the need for cross-cultural validation, digital innovation, and early identification to improve research and applied practice.