Harmonies can become either static or developmental. Static harmonies indicate relatively constant levels of tension or relaxation and often tend to result from chords formed of equidistant intervals and connected by relatively weak root relationships. Nonetheless, static harmonies can build tension--through the use of repetition. In the tune, "Moanin", for example, the IV-I response of the call-response pattern is repeated throughout the A section (even the voicing will usually remain the same!) Yet the tension grows throughout the section by the simple process of re-emphasis through repetition. Developmental harmonies involve the careful distribution of both tension and relaxation toward a specific harmonic goal and seem to require chords of different-sized intervals with a variety of weak/strong root relationships. Many compositions contain sections of both static and developmental progressions (the B section of "Moanin" is developmental, for example).
As aids to static and developmental chord relationships (expanded further in the links above), harmonic tension and relaxation can also be developed through chord alterations, extensions and substitutions.