Subject metadata, a controlled vocabulary, is considered as an important element in a bibliographic record to enhance the precision of information search results. Yet, the subject search is the most complicated searching task for end-users. However, the information scientists or institutions have endeavored to formulate language-specific subject headings according to their requirements, but due to lack of coordination among them, uniformity and consistency not sustained. This book uncovers the existing practice of assigning subject headings for Bengali documents to perform the subject search in online catalogs. Moreover, the suitability of subject headings for retrieval of resources has ascertained from the users' point of view. It also provides the framework compatible with international standards to accommodate the authority control in the multilingual systems. This book confirms that the principles and rules are a fundamental requirement for optimal use of subject headings in online catalogs. Thus the web-enabled subject authority control can be applied intelligently for the retrieval of knowledge resources.