Synapses are the main sites of communication in the nervous system and are also critically involved in several major brain diseases. The conference aims to increase our understanding of the fundamental molecular and cellular mechanisms of synaptic transmission, to elucidate how synaptic transmission shapes neuronal network activity, and to link basic science on synapses to disease aspects. Several brain diseases, such as neurodegenerative diseases, mood disorders, schizophrenia, and autism spectrum disorders, are emerging as synaptopathies, but the precise mechanisms are unknown. We will bring together a group of scientists who all are highly interested in synaptic function, but examine synapses at different levels, look at them from different perspectives, and use different approaches (molecular biology, imaging, optogenetics, subcellular electrophysiology, modeling, and many others). The program will have two keynote lectures entitled "Synaptic transmission: from molecular machines to network activity" and eight sessions that address different aspects of synaptic signaling, including mechanisms of exocytosis, presynaptic terminals, synaptic spines, pre- and postsynaptic plasticity, connectomics, synaptic diseases, and function of synapses in microcircuits and neuronal networks in vivo. The conference will bring together a diverse group of investigators who are at the absolute forefront of their field, and will provide ample opportunities for junior scientists to present their work in poster format. Furthermore, some poster presenters will be selected for short talks. The newly established Gordon Research Seminar (GRS) directly preceding the GRC will make this meeting particularly attractive for graduate students, enabling them to directly exchange ideas with world-class leading scientists. Past participants have lauded this GRC for the uniquely high quality of unpublished data being presented and for the collegial and interactive atmosphere where scientists at all levels felt welcome to join in the discussion of most recent advances in the field.