To discover areas within the Swedish indexing system for children’s and youth literature that could limit the possibility to find books about a certain subject or of a particular type, and to identify factors that could complicate the development of Swedish subject headings and the genre/form system for children is the aim with this study. The research area is explored by analyzing information about the indexing process of books for children and youths in Sweden today, and information about the development of the specific indexing system. Specialist librarians connected to Svenska barnboksinstitutet have contributed to the empirical data and Mai’s domain-centered approach to indexing is used as a theoretical framework. Some areas within the indexing system that could have a negative impact on the quality and consistency of the indexing and thus reduce the searchability are shown. Using Lancaster’s suggestions about what could effect the indexing quality it is discussed that the indexing vocabulary, the document, the indexer and the “process” could contribute to the problems. Another finding that could cause inconsistency is the occurrence of subdomains within the nationwide domain. Factors that could complicate the development of the indexing system are also identified. These factors can be linked to historical and contemporary, cultural, linguistic and societal aspects, but also to the specific target group. The findings indicate that maintaining a system with updated, neutral indexing terms adapted to the needs of the target group requires a continuous and coordinated work, responsiveness, awareness of societal change, and linguistic sensitivity