Solution TMI(TM) precursor has been protected by a US patent since 1993 (US patent 5,232,869, 1993) and is widely used but up to now precise vapour pressure measurements were missing. In cooperation with Epichem Ltd. we have measured, for the first time, the vapour pressure of all the components of this TMI precursor source: N,N-dimethyldodecylamine, solid trimethylindium (TMI), adduct 1:1 TMI-N,N-dimethyldodecylamine and Solution TMI(TM) in order that the performance of this source for MOVPE growth may be better understood. The measurement of vapour pressure was performed in the technologically important temperature range from 273 up to 313 K. (C) 2004 Elsevier B.V. All rights reserved.