Abstract: The Finnish BFFI vocabulary is an extended vocabulary of BIBFRAME. The overall changes in BFFI compared to BIBFRAME are manifested in the reduction of classes and attributes. Specific changes include splitting the work class, adding new RDA concepts, and introducing new classes and properties of aggregates. BFFI is closer to the new RDA in terms of hierarchy and concepts, but there are also differences. The construction of BFFI vocabulary shows that, with the continuous maturity of the bibliographic framework BIBFRAME, the library community has developed a deeper understanding and more advanced application of localized implementation.