The thermolysis of organotin compounds R₃SnX (R=Ph, Bu, Cy, Neo, Bnz; X=Cl, OSnRa, SnR₃, O₂CR'), R₂"SnO and R"Sn(O)OH (where R"=Bu, Oct) has been investigated by thermal analysis, gas chromatography and Mössbauer spectroscopy. Several decompositions of R₃SnX occurred via disproportionation to the tetra- and di-organotin products. Organotin compounds were successfully encapsulated into sized metal acetate glasses, with little or no decomposition of the organotin. Both halide/acetate and oxide/acetate exchanges occurred in the melt; partial exchange was realised with sterically hindered trineophyltin chloride. Tin-tin and tin-sulphur bonds were unaffected by the acetate melt; and only tin-carbon bond cleavage found was with tribenzyltin chloride. Mössbauer spectra of the compounds encapsulated into the acetate glass generally had identical spectra to the pure compounds in those cases where no exchange occurred; in contrast when anion exchanges occurred the trapped organotin compounds had different Mössbauer spectra to those of the starting material and the exchange product. Reactions between BX₃ (X=F, Br or Cl) and TiCl₄ with R₃SnCH₂CH=CHR' (I, R=Me, Bu or Cy; R'=H or Me) were studied by NMR spectroscopy. Allyl group/bromide exchanges occur between I and BBr₃ at (<50°C), at higher temperature (ca - 10°C) I (R=Me or Bu but not Cy) reacts further to give R₂SnBr₂. Reaction between BCl₃ and I (R=Bu; R'=H) at (<50°C) proceeded to form only Bu₃SnCl. No allyl group/fluorine exchange products were detected from the reaction between I and BF₃.Et₂O below -20^OC, however at 25°C I (R=Me; R'=H) reacts readily with BF₃.Et₂O, the predominant soluble tin species being Me₄Sn. Compounds I and TiCl₄ at 30°C rapidly produce R₃SnCl and (RCHCHCH₂)TiCl₃.