Chapter 6 provides a systematic analysis of the formal logic, modular structure, compound stripe arrangements, and color correlations in traditional Atayal textile patterns, demonstrating the tribe’s sophisticated design thinking. The chapter begins by noting that the seemingly simple geometric motifs conceal a complex, almost formulaic logic rooted in cultural consciousness. Through case studies of selected textiles (e.g., from Klesan, Musha, and Truku), the author identifies foundational shape modules—diamonds, mountains, crosses, and X-forms—and distills nine modular construction types used to build pattern systems. These modules are interchangeable and serve as a basis for creating new combinations and complex designs. In analyzing compound stripe arrangements, the study categorizes eight layout principles, including staggered reflection, interval reflection, vertical repetition, and grouped repetition, which demonstrate the structural precision and aesthetic regularity in Atayal design. Some irregularities found in pattern sequences are attributed to manual variation and cultural flexibility, rather than error. Color analysis reveals the Atayal’s use of triadic or multi-color contrasts employing “juxtaposition additive color mixing” to enhance visual vibrancy and spatial layering. Patterns and colors interact systematically, with color boundaries often enhancing or separating visual motifs, sometimes creating gradient or halo effects. Finally, the chapter examines the relationship between pattern styles and the geographic distribution of subgroups within the Atayal people. It reveals how migration, intermarriage, and oral traditions have influenced the stylistic exchange and continuity of pattern systems across subgroups like Klesan, Malepa, Bunsui, Beishi, and Truku.