The review deals with theoretical derivation, based on conventional equations and reduced parameters, of relationships describing the analysis time and the related pressure drop. On the basis of derived equations, methods of minimizing the GC analysis time are discussed. Reduction of the column inner diameter and using hydrogen as carrier gas is the best approach to increasing the separation speed in GC. The vacuum outlet operation of capillary columns allows in some situations a further shortening of the analysis time. The effect of reduction of the column inner diameter on chromatographic zone broadening, detection limits and sample capacity is also discussed.