A system comprising: an implantable medical device, IMD, comprising a memory; a programmer configured to communicate with the IMD and providing a user interface configured to display a plurality of different stimulation sensations, wherein each stimulation sensation is associated with respective values of a set of therapy parameters, each set of therapy parameters including a stimulation pulse width and a stimulation pulse amplitude; and receive user input that represents a selection of a stimulation sensation from among the plurality of different stimulation sensations; and wherein the IMD comprises: a processor configured to, in response to user input, select the respective values of the set of therapy parameters; and a stimulation generator configured to generate stimulation according to the selected values of the set of therapy parameters; wherein the user interface is further configured to produce an interactive control to receive the user input, wherein the user input further comprises an adjustment of the interactive control that is representative of an adjustment of at least one characteristic of the selected stimulation sensation, wherein the processor is further configured to adjust the selected values of the set of therapy parameters and control the stimulation generator to generate stimulation according to the adjusted values of the set of therapy parameters in response to the adjustment of the interactive control, and wherein the processor is configured to control the stimulation generator to adjust values of stimulation pulse width and stimulation pulse amplitude according to a predefined function stored in the memory in response to the adjustment of the interactive control, the predetermined function maintaining a predetermined ratio of values of pulse amplitude and pulse width or constraining the pulse amplitude and pulse width to values which capture target neural tissue. an implantable medical device, IMD, comprising a memory; a programmer configured to communicate with the IMD and providing a user interface configured to display a plurality of different stimulation sensations, wherein each stimulation sensation is associated with respective values of a set of therapy parameters, each set of therapy parameters including a stimulation pulse width and a stimulation pulse amplitude; and receive user input that represents a selection of a stimulation sensation from among the plurality of different stimulation sensations; and wherein the IMD comprises: a processor configured to, in response to user input, select the respective values of the set of therapy parameters; and a stimulation generator configured to generate stimulation according to the selected values of the set of therapy parameters; a processor configured to, in response to user input, select the respective values of the set of therapy parameters; and a stimulation generator configured to generate stimulation according to the selected values of the set of therapy parameters; wherein the user interface is further configured to produce an interactive control to receive the user input, wherein the user input further comprises an adjustment of the interactive control that is representative of an adjustment of at least one characteristic of the selected stimulation sensation, wherein the processor is further configured to adjust the selected values of the set of therapy parameters and control the stimulation generator to generate stimulation according to the adjusted values of the set of therapy parameters in response to the adjustment of the interactive control, and wherein the processor is configured to control the stimulation generator to adjust values of stimulation pulse width and stimulation pulse amplitude according to a predefined function stored in the memory in response to the adjustment of the interactive control, the predetermined function maintaining a predetermined ratio of values of pulse amplitude and pulse width or constraining the pulse amplitude and pulse width to values which capture target neural tissue. wherein the processor is further configured to adjust the selected values of the set of therapy parameters and control the stimulation generator to generate stimulation according to the adjusted values of the set of therapy parameters in response to the adjustment of the interactive control, and wherein the processor is configured to control the stimulation generator to adjust values of stimulation pulse width and stimulation pulse amplitude according to a predefined function stored in the memory in response to the adjustment of the interactive control, the predetermined function maintaining a predetermined ratio of values of pulse amplitude and pulse width or constraining the pulse amplitude and pulse width to values which capture target neural tissue.