This is an announcement for the paper "A classification of Tsirelson type spaces" by Jordi Lopez Abad and Antonis Manoussakis. Abstract: We give a complete classification of mixed Tsirelson spaces T[( F\_i, theta\_i)\_{i=1}^r ] for finitely many pairs of given compact and hereditary families F\_i of finite sets of integers and 0<theta\_i<1 in terms of the Cantor-Bendixson indexes of the families F\_i, and theta\_i (0< i < r+1). We prove that there are unique countable ordinal alpha and 0<theta<1 such that every block sequence of T[( F\_i, theta\_i)\_{i=1}^r ] has a subsequence equivalent to a subsequence of the natural basis of the T( S\_{omega^alpha},theta ). Finally, we give a complete criterion of comparison in between two of these mixed Tsirelson spaces. Archive classification: Functional Analysis; Logic Mathematics Subject Classification: MSC 46b20, 05d10 The source file(s), lop-man.tex: 131413 bytes, is(are) stored in gzipped form as 0510410.gz with size 37kb. The corresponding postcript file has gzipped size 150kb. Submitted from: abad@logique.jussieu.fr The paper may be downloaded from the archive by web browser from URL http://front.math.ucdavis.edu/math.FA/0510410 or http://arXiv.org/abs/math.FA/0510410 or by email in unzipped form by transmitting an empty message with subject line uget 0510410 or in gzipped form by using subject line get 0510410 to: math@arXiv.org.