This is an announcement for the paper “Operators on Bourgain-Delbaen's spaces” by Daniele Puglisi<https://arxiv.org/find/math/1/au:+Puglisi_D/0/1/0/all/0/1>. Abstract: We prove that, for a suitable choice of real numbers $a, b$, every operator from $\ell_2$ to $X_{a, b}$ and from $X_{a,b}$ to $\ell_2$ must be compact, where $X_{a,b}$ is the Bourgain- Delbaen's space. The paper may be downloaded from the archive by web browser from URL https://arxiv.org/abs/1609.03270