This study investigates what is perceptually the most optimal way to create a temporal color transition between two colors. The first experiment measured the ability to distinguish between two temporal color transitions. The reference transition was a linear interpolation between two colors in CIELab, the test transitions were arcs defined in different planes going through the linear transition. Discrimination thresholds ranged between 2.5 and 10.5 ΔE_ab, dependent on the color pair, direction and duration of the transition. In the second experiment, several perceptually different color transitions were evaluated. The most preferred transitions were a linear transition in CIELab and a linear transition in RGB. This suggests that appealing temporal color transitions can be created without complicated calculations.