This paper provides an introduction into understanding the relative merits, characteristics, including economics, of photovoltically powered water pumping systems. Although more than 10,000 Photovoltaic pumping systems are known to be operating throughout the world, many potential users do not know how to decide whether or not photovoltaic pumping systems are an alternative option for them. This paper provides information on feasibility assessment, and system procurement so that the reader can made an informed decision about water pumping systems, especially those powered with photovoltaics.