Biofilms are spatially structured bacterial communities that contribute to chronic bacterial diseases. Many cells within the biofilm are shielded from host defenses and drugs. In addition, multiple species frequently co-occur and interact in a polymicrobial biofilm. We are very interested in the biofilm development and the transcriptome-wide responses to antimicrobial treatments on a single-cell level. By employing single-cell RNA sequencing in conjunction with time-lapse imaging, we aim to create single-cell gene expression maps of model single- and multiple-species biofilms. We will also unravel how these responses change in the presence of interacting or competing species.