The current conventions for test score reliability coefficients are unsystematic and chaotic. Reliability coefficients have long been denoted using names that are unrelated to each other, with each formula being generated through different methods, and they have been represented inconsistently. Such inconsistency prevents organizational researchers from understanding the whole picture and misleads them into using coefficient alpha unconditionally. This study provides a systematic naming convention, formula-generating methods, and methods of representing each of the reliability coefficients. This study offers an easy-to-use solution to the issue of choosing between coefficient alpha and composite reliability. This study introduces a calculator that enables its users to obtain the values of various multidimensional reliability coefficients with a few mouse clicks. This study also presents illustrative numerical examples to provide a better understanding of the characteristics and computations of reliability coefficients.