An ablation planning system includes a user interface (104) configured to permit selection of inputs for planning an ablation procedure. The user interface is further configured to incorporate selection of ablation probes and one or more combinations of ablation powers, durations or parameters applicable to selected probes in the inputs to size the ablation volumes. The user interface includes a display for rendering internal images of a patient, the display permitting visualizations of the ablation volumes for different entry points on the internal images. An optimization engine (106) is coupled to the user interface to receive the inputs and is configured to output an optimized therapy plan which includes spatial ablation locations and temporal information for ablation so that collateral damage is reduced, coverage area is maximized and critical structures are avoided in a planned target volume.