Considering that the absence of participants in group therapy process, especially when dealing with closed groups, ultimately interfere with group dynamics, the study aimed to investigate the absence of participants during the therapeutic process developed in a group of young people diagnosed with social phobia. The group in question was composed of university students diagnosed with Social Anxiety Disorder in a university hospital in a midsize city in the state of Sao Paulo. From the session analyzed by means of psychoanalysis, it was understood that absences are not mere forgetfulness or facts without any impact on group dynamics. An external event (failure) was brought into the group space, raising the assumption of new placements of participants who were present and acknowledging the need for all participants (missing or not) to be duly accepted, observed and assisted in the therapeutic process.