Anybody who organises concerts or publishes, reproduces, performs, broadcasts or otherwise disseminates music is automatically a client of SUISA’s. Even the owner of an aerobic studio who plays music during lessons is a client. Anybody using music publicly needs a licence and is therefore a client of SUISA’s.
If you use music in private, i.e. within a small circle of family and friends, you do not need a licence. All other uses are considered public uses and require a licence from SUISA. The organiser is responsible for obtaining the licence for public use.