A change in temperature can have a significant effect on relative retention in gas chromatography (GC), in many cases leading to reversals in band elution order. Maximum resolution can often be obtained at an intermediate temperature or heating rate. Many samples can benefit from the use of multiramp temperature programs that optimize the heating rate for each band in the chromatogram. Because these temperature- related changes in separation selectivity can be used as a basis for developing a final GC method, computer simulation of temperature optimization can greatly simplify GC method development. Several practical examples of this approach are presented