Four examples of multimodality diagnostics for groups in the UMaS region. Vertical bars depict individual galaxies in each group. The solid lines indicate the best Gaussian mixture for for radial velocities distributions in km s^-1. The dashed lines show the individual components of the multimodal systems. The dotted lines indicate the average Gaussian curve for 1000 resamplings of groups 03 and 34, unimodal but non-Gaussian systems.