Social, emotional, and behavioral (SEB) skills comprise a broad set of abilities that are essential for building and maintaining relationships, regulating emotions, selecting and pursuing goals, or exploring novel stimuli. Toward an improved SEB skill assessment, Soto and colleagues recently introduced the Behavioral, Emotional, and Social Skills Inventory (BESSI). Measuring 32 facets from 5 domains with 192 items (assessment duration: [approximately]15 min), BESSI constitutes the most extensive SEB inventory to date. However, so far, BESSI exists only in English. In three studies, we comprehensively validated a novel German-language adaptation, BESSI-G. Moreover, we expanded evidence on BESSI in three ways by (1) assessing the psychometric properties of the 32 individual skill facets, in addition to their domain-level structure; (2) providing first insights into the temporal stabilities of the 32 facets over 1.5 and 8 months; and (3) investigating the domains' and facets' associations with intelligence, in addition to personality traits. Results show that BESSI-G exhibits good psychometric properties (unidimensionality, reliability, factorial validity). Its domain-level structure is highly similar to that of the English-language source version. The facets show high temporal stabilities, convergent validity with personality traits, and discriminant validity with fluid and crystallized intelligence. We discuss implications for research on SEB skills.