Silence is a common social interaction in psychotherapy which also has great impact on psychotherapy outcomes, especially at the beginning stage of psychotherapy where therapists and clients begin to build their therapeutic alliances for the first time. However, the few existing studies have shown that many practising therapists either failed to deal with silence in their researched sessions or were self-reported to be not confident in doing so. Therefore, this research investigates different triggers for silence at the early stage of psychotherapy with young adults and their surrounding conversation sequences with the conversation analysis method. Data includes two sessions of psychotherapy with two young adult clients. The results identified four triggers for silence: conflict, confusion, challenge and support triggers, which improves the understanding of this social interaction.