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We describe the formation and emission of endohedral fullerenes, Cs@C60+ and Cs@C70+, following a single collision of Cs+ ion with a sub-monolayer of C60 on gold and silicon surfaces and with a sub-monolayer of C70 on gold. A continuous low energy (E0=35–220 eV) Cs+ ion beam hit the C60 covered surface and the collisional formation and ejection of the endohedral Cs@C60+ complex, within a single Cs+/C60 collision, was observed and characterized. The steady state C60 coverage is shown to be in the sub-monolayer range. The instantaneous rise of the Cs@C60+ signal (by a factor of 103) with the Cs+ beam onset clearly demonstrate the single collision nature of the combined “atom penetration/endo-complex ejection” event. The fullerene molecule is actually being picked up off the surface by the penetrating Cs+ ion. The evidence for the trapping of the Cs+ ion inside the fullerene cage is given both by the appearance of the Cs@C60−2n+ (n=1–5) sequence and its termination at Cs@C50+. Similar experiments were carried out with nearly pure (98%) C70 sub-monolayer on gold. Both the Cs@C70−2n+ and C70−2n+ (n=0,1,2,…) fragmentation sequences were observed. Cs@C60+ and C60+ signals appeared strongly enhanced in these sequences. We believe that the experimental results presented here provide a first example of a single collision pick-up scattering (Eley–Rideal type) involving the formation and ejection of an endo-complex. [Copyright &y& Elsevier]