Group synchronisation in choir performance was studied using motion capture. The choir consisted of South-African experts and Finnish novices. 4+4 participants’ movements were recorded during a performance of a traditional song and choreography. The aim of the study was to: 1) describe possible differences in movement implementation between the two groups; 2) investigate synchronicity between all participants and within and between each of the two groups; 3) visualise the dynamics of interpersonal influence. Preliminary results indicate that simple indicators such as cumulative distance and position as a function of time reveal differences in implementation of choreography between the groups. Movements were very synchronous, but cross-correlations of the vertical velocities of markers revealed a subtle phase difference between individuals and shows that the expert group was more coherent than the novices, as was expected. This could be due to having more attentional resources to spend on coordination, as the musical and movement material is more familiar to the experts than the novices. Finally, the interpersonal interaction was visualised using windowed cross-correlation. This suggests that the temporal relationship of movements reflects the participants’ mutual adaptation to each other’s subtle timing perturbations, and that this adaptation is a dynamic process.