Beak and feather disease virus (BFDV) is a poorly studied virus considering its worldwide distribution and devastating effect on native and endangered avian species.  The virus consists of two proteins, a replication protein, and a capsid protein (Cap).  As the virus possesses so few proteins Cap must be multifunctional, including a role in nuclear localization of viral molecules.  At the N-terminus of the protein is a nuclear localizing signal (NLS), however, the specific mechanism for import into the nucleus has not been demonstrated.  The large amount of arginine residues resemble a sequence consistent with other classical NLSs that bind with nuclear importin alpha (Impa).  Crystallography was applied to determine the pathway of nuclear entry for Cap.  To determine if the Cap NLS is capable of binding Impa, a synthetic peptide, representing a large portion of Cap NLS, was complexed with an Impa isolate that has been crystallized for several previous experiments.  Crystallization of the complex allowed structural determination, providing further insight to the nuclear localization of Cap.  Three NLS regions present in the Cap sequence, NLS1, NLS2, and NLS3, have been identified and classified as bipartite, however, only binding in the major site of Impa is seen in this data.  The NLS peptide represents NLS1 and NLS2 of the entire NLS region of Cap.  The monopartite binding could be due to the lack of NLS3, which has a KR motif typical of NLSs that bind the minor site.  Conversely, the region containing the KR motif is predicted to form a beta-sheet, and, therefore, may not be available to bind.  It was not previously demonstrated that NLS1 and NLS2 were capable of nuclear localization of Cap without NLS3, and, although the bond strength may not be optimal without NLS3, this data shows that NLS2 is capable of binding Impa.