A new paper by Edward Broadhurst on "Polymorph evolution during crystal growth studied by 3D electron diffraction" has been published in IUCRj. The work aims to highlight the powerful technique of combining 3D electron diffraction (3DED) with cryoTEM to studydynamic systems in situ. The present methods show that it can be applied to study dynamical chemical processes. Here we have focused on polymorphism, but the same methods might also be applicable to reaction mixtures. Publication date 17 Jan, 2020