Because of degradation and overgrowing of natural ecosystems, plant biodiversity, which is essential for breeding work directed to amelioration of agricultural as well as market value characteristics, is highly endangered. The paper focuses on the main directives and significance of national research program for collecting, maintenance, preservation and evaluation of autochtonous and/or introduced genetic material of medicinal and aromatic plants in Slovenia. The first stage of the program foresees monitoring of natural populations, their characterization and "in situ" conservation of evaluated autochtonous plant material. In order to manage extensive data network in most efficient way, our working group has recently developed a relational database, named MEDPLANT, established for floristic, faunistic, taxonomic and analytic data input for medicinal and aromatic plants (MAP) of Middle European and Mediterranean regions. MEDPLANT is aimed at screening those high potential native populations of medicinal and aromatic plants, which meet raw material quality requirements in different branches of processing industries (i.e. phytoterapy, food industry, phytocosmetics). MEDPLANT system works on relational databases principles: collected data are arranged according to their characters in appropriate databases (systematics, geography, habitats, pedology, phytocoenoses, chemical analyses, varieties/cultivars). Pointers, which connect specific data in these databases enable establishing mutual relationships between required data in the network. The data on first Slovenian expedition, held in July 1999, are presented.