Invisalign is an excellent choice for the correction of minor to moderate crowding without requiring any extractions. These patients had some crowding and were not happy with the arrangement and alignment of their teeth. After taking photographs and moulds of their teeth, we were able to construct a 3D computer simulations of the planned movement and most importantly a preview of the final result. Changes to the treatment can be made at this stage. Once satisfied, the almost invisible aligners can be manufactured ready for treatment to begin.