Whereas the OPAC Model defines the system architectures, the Library
Systems Architecture Planning Model (LSAP Model) provides a tool for
choosing among them. The system characteristics defined in the reference
model are included to meet real-world needs, such as providing access to
another library’s holdings or preserving local autonomy. The LSAP Model
follows from the Reference Model by making explicit the connection between
a set of system characteristics and a set of environmental characteristics