AMICUS is the National Library's new integrated bibliographic system. The initial phase of development, released in the second quarter of 1995, supports cataloguing and catalogue products, bibliographic searching and customer information management. The search module is implemented as a Z39.50 server that accesses the two database engines integrated into AMICUS: a relational database for bibliographic data management and a full text database for keyword searching and future full text access. An overview of the AMICUS applications is followed by a brief introduction to the modelling of AMICUS bibliographic information in the relational database. A more detailed description of the architecture of the AMICUS search engine is given, describing components, internal messaging, query analysis, optimization, semantic mapping and record conversion. A description of the three AMICUS clients concludes the paper.