Silicon photonics is a promising platform for implementing quantum information processes. Since the development of the first integrated waveguide photon pair sources in 2006, a lot of progress has been made towards demonstrating the operation of the different functionalities required to implement universal quantum computation on this platform. I will review the state of the art and will then highlight the current challenges, which are for most of them not “quantum” at all, but are rather extraordinary optical and photonics engineering puzzles.