The world pharmaceutical market^ which was valued at $247.9 billion In 1994, is forecasted to grow to $342 billion by 1999. High throughput screening(HTS) is attracting attention as a novel methodology for new drug discovery. HTS is expected to expand the scale from one thousand to one hundred thousand times the current level by utilizing robots，laboratory information management systemsCLIMS), various sources to screen natural products(plant extracts, secondary microbial metabolites), peptide combinatorial libraries and combinatorial organic synthesis(COS) for new therapeutics. Instrumentation, target selection, source material，sample preparation，primary and secondary assays，isolation，purification an structure elucidation are all important for HTS.