Initiation of smooth pursuit eye movements was studied using imaginary targets defined by pairs of small spots ("cues") moving together in step-ramp motion. The arrangement of cues and imaginary target were either "two-sided"--cues far apart and imaginary target midway between, or "one-sided"--cues 4 deg apart and imaginary target to one side of the cue pair. (1) Pursuit of two-sided stimuli was much better than pursuit of one-sided stimuli and was often as good as pursuit of a real foveal target. (2) Experiments with various cue configurations suggest an attribute required for vigorous pursuit: "foveal enclosure". Configuration information is available to the pursuit system immediately after the onset of motion. (3) Pursuit of imaginary targets is markedly degraded by a background; the effect is strongest for a background at the fovea and weaker for an eccentric background, including one at the cue location.