This paper describes a computer program which performs all head calculations needed to write a pump specification suitable for a vendor inquiry or purchase order. The program is written for use with the Texas Instruments TI-59 calculator and the compatible PC-100C printer. A unique feature of the program is that it is self-prompting. It asks a series of question that elicit the necessary data from the user. The program proceeds in this manner until all the parameters required to specify a pump have been calculated. An example is given together with sample calculations.