There are a large number of different types of flexible couplings available for use in the pump industry today. Each has its own features and benefits, but all are required to perform three primary functions: connect two shafts, transmit rotary power, and accommodate shaft misalignment. This document outlines pumping industry standard practices to select flexible couplings based on application requirements. Along with basic selection techniques, this document will review the most common styles of couplings found on pump applications across different industries today. The document also provides the user with general guidance on the installation and maintenance requirements of each coupling type.