"The early growth of supermassive black holes": Supermassive black holes with masses of several billion solar masses are already in place at z~6-7. I will discuss models and numerical simulations of the early growth of these supermassive black holes and their environment with an emphasis - on the role of the formation of massive seed black holes by direct collapse in DM haloes with virial temperatures above the atomic cooling threshold, - and the role of AGN feedback in driving outflows and regulating the growth of supermassive black holes.