The application of Laser Induced Breakdown Spectroscopy (LIBS) to real-time, in-situ and remote analysis of trace amounts in liquid samples is described, to be used for example in harsh or difficult-to-reach environments within industry for the analysis of pollutants in water. Numerous elements, including a range of toxic heavy metals, have been measured over a wide range of concentrations. Detection limits usually are in the range of a few parts per million; for several elements even lower limits could be realized. The analysis system is based on a fiber delivery assembly which is capable to both deliver the laser light to, and to collect the micro-plasma light from the target area, up to 30 m. Alternatively, a telescopic arrangement for in a 'line-of-sight' arrangement was employed. In order to provide quantitative data in the evaluation of laser generated plasmas, parameters such as electron densities, plasma temperature, line shape functions, and others need to be known; their measurement and determination are outlined. For internal standardization and the generation of concentration calibration curves, reference lines of carefully chosen elements were used.