It is automatically constrained into dynamic motion by trines and conjunctions. Sextiles and semi-sextiles indicate the possibility to achieve the same, but it requires a decision and commitment from the bearer of this aspect. On the downside, this energy will be aggravated into out of control situations by squares and oppositions. The presence of quincunx suggests unawareness. In this case, this energy can operate unconsciously.
For example, you have Sun sesquiquadrate Jupiter in your chart. This suggests a tendency to have grandiose projects, but little desire to pay attention to details. You rely on your luck too much. This is a recipe for disaster on the long term. But, if Saturn is trine your Sun or Jupiter, it will compensate for this issue. This combination suggests strong leadership skills for long-term projects.
Or, say you have Moon sesquiquadrate Uranus in your birth chart. You are one of a kind and you won't fit any mold. That's perfectly fine, you are an independent and original being, experiencing unique emotions continuously. However, if Venus is square your Moon or Uranus, then this suggest high internal turmoil damaging all your relationships. You have a very hard time keeping your uniqueness and sensitivity under your control.
Related aspects: square, semi-square, t-square and grand cross
Other minor & rare aspects: grand trine, quincunx & inconjunct, quintile & biquintile, semi-sextile and yod