The ready-made garments (RMG) sector of Bangladesh has developed immensely under the broad radar of the export market, and its size is beyond imagination. Unfortunately, there has been no study that explores the whole universe of the RMG sector of Bangladesh rather the story of the RMG sector often involves the export market only. The discussion of this paper intends to explore the methodology of unboxing the whole universe of the RMG sector of Bangladesh that includes small and medium-sized manufacturing and processing units that are often involved with subcontracting for other factories (producing for the export market as well as domestic market), are suppliers of the domestic market, are producers of accessories, and are providing backward linkages and associated services. The discussion addresses that along with export-oriented RMG factories there exists an unexplored and unboxed universe of manufacturing and processing units associated with the RMG sector of Bangladesh that contributes to investment, employment, trade, export, and the economy as a whole, all of which remains unaccounted for.