Herein we report the results of an investigation of the trajectories of horizontally coplanar droplet pairs of similar charge, falling under the influence of gravity, drag, and electrostatic forces. Experiments were conducted using ethanol droplets that were generated electrostatically from the tips of two parallel needles. These droplets were subject to an external electric field and an initial electrostatic force in the vertical, downward direction, and an interdroplet electrostatic repulsive force in the horizontal direction. A model was developed to predict the measured trajectories. Within the range of applied potential differences investigated (from 1–3 kV), the theory and experiment were found to agree to within approximately 5%. The results also showed that the droplet trajectory was influenced noticeably by the axial electrostatic force on the droplet as it departed from the needle.