Described herein is method for the operation and the expansion of a network of lights, each light in the network including a control module which is assigned to a group, each control module being in communication with a group controller as well as control modules in the same group. The network can be expanded by installing (19) new lights with their associated control modules, and each new control module scans (20) its environment and transmits environmental information to a central server where the environmental information is analysed and the new control modules are allocated (21) into groups. After allocation to a group in which control modules may be moved from one group to another or a new group is formed, the new control modules are available for normal operation (22). This process is repeated for each new light and associated control module.