A time domain method has been developed for treatments of vortex dynamics in all classes of blade-blade interaction problems. A new vortex impingement condition is introduced to the discrete vortex tracking scheme and was found most effective in handling the vortex-airfoil interaction and the blade-blade interaction (BBI) problems. Present results are verified with all classical solutions and are found in good agreement with almost all existing solutions. The present BBI study concludes that any front blade movement will induce a strong interaction between the wake and the rear blade; hence, it alters drastically the lift response and the wake structure. Any rear blade movement only induces a weak interaction, hence rendering the blade system ineffective