The free living nematode Caenorhabditis elegans represent one of the best investigated model organisms in modernbiological research. Among the numerous advantages, the worm is inexpensive to cultivate, its genome iscompletely sequenced and a broad range of molecular and genetic tools are available. The worm has a short lifespanwhere it progresses from eggs via four larval stages to fertile adults in three days allowing rapid experimentation.Although C. elegans is a relative simple multicellular organism, it contains a variety of tissues like a nervoussystem, muscles and intestine, which make it a suitable system for various fundamental studies. The worm istransparent at every stage of their life cycle that makes it easy to analyse expression patterns of proteins within theworms by using markers such as green fluorescent protein. RNA interference which allows the investigation of genefunction by specific suppression of proteins is feasible with these organisms. There are several applications to theusage of C. elegans in medical research. Accordingly, the worm is an established model to study diseases such asparkinson’s, obesity, muscular dystrophy or biological processes such as aging. C. elegans is also useful for drugscreening such as antihelminthics. The paper will discuss the identification of the first metazoan polyaminetransporter which is of potential pharmacological importance.