From an out-of-school perspective, the book studies private supplementary tutoring, also widely known as shadow education within the Chinese education landscape. The author presents an organizational ethnography of Smart English, a private English tutoring center in Beijing. Using the concept of "organizational legitimacy" from organizational institutionalism as its framework, the study provides a detailed account of the center's daily operations. It examines how the organization manages its legitimacy while navigating regulations, providing private supplementary tutoring, and addressing public skepticism. The book documents the typical operations of such institutions in Chinese mainland before stringent regulations disrupted their activities, serving as a "salvage" record. This book enriches educational ethnographies and will appeal to academics of shadow education, Chinese education, and ethnography.