We have performed ion mobility measurements on silver cluster cations Ag-n(+) generated by pulsed laser vaporization. For clusters with n < 12. experimental cross-sections are compared with theoretical results from density functional and MP2 (Moller-Plesset) calculations. This comparison allows structural assignment. We find that room temperature silver cluster cations have planar structures for n = 3-4. Starting at n = 5 they form three dimensional structures. The structures are compared with predictions by Bonacic-Koutecky et al. and the respective results obtained in a previous study for gold clusters. (C) 2002 Elsevier Science B.V. All rights reserved.