Mass selected cluster deposition is discussed with respect to three questions: what is the integrity of the clusters after deposition; are they uniform in terms of size and isomerisation; and finally what is the influence of the support on the clusters? The answer to these questions will depend on the strength of cluster media interaction and we have chosen two extreme cases the inert rare gases on one hand and metal surfaces on the other. Three examples are given: Raman studies as well as low-temperature STM give structural information on the deposited clusters, while other optical spectroscopies (absorption and fluorescence) yield information on the electronic structure of the clusters.