Research has shown that interactions in group therapies for people with schizophrenia are associated with a reduction in negative symptoms. However, it is unclear which specific interactions in groups are linked with these improvements. The aims of this exploratory study were to i) develop and test the reliability of using video-annotation software to measure interactions in group therapies in schizophrenia and ii) explore the relationship between interactions in group therapies for schizophrenia with clinically relevant changes in negative symptoms.