This is an announcement for the paper "The convex hull of a Banach-Saks set" by C. Ruiz, J. Lopez-Abad and P. Tradacete. Abstract: A subset $A$ of a Banach space is called Banach-Saks when every sequence in $A$ has a Ces{\`a}ro convergent subsequence. Our interest here focusses on the following problem: is the convex hull of a Banach-Saks set again Banach-Saks? By means of a combinatorial argument, we show that in general the answer is negative. However, sufficient conditions are given in order to obtain a positive result. Archive classification: math.FA math.CO math.LO Mathematics Subject Classification: 46B50, 05D10 Remarks: 29 pages Submitted from: abad@icmat.es The paper may be downloaded from the archive by web browser from URL http://front.math.ucdavis.edu/1209.4851 or http://arXiv.org/abs/1209.4851