Embodiments of the present invention provide an electroporation system comprising an electroporation probe having at least two contiguous electrodes configured to be inserted into biological tissue for electroporation treatment, and a pulse generator electrically connected to the probe and configured to drive the electroporation probe using a sequence of one or more electric pulses to cause current transmission through the probe and induce a non-uniform electric field in the biological tissue proximate the probe electrodes. Treatment tissue can be targeted by controlling the probe configuration, carrier solution characteristics and parameters of the electroporation pulse sequence to achieve predictable electroporation outcomes. This electroporation control method can also reduce potentially toxic effects of electroporation treatment.