Trade studies and close examination of direct detection laser crosslinks for a number of applications have shown that the development risk is comparable to or lower than that of RF systems. Since laser crosslinks offer significant advantages over RF crosslinks for the same applications, the specification of laser crosslinks is a good choice. The reason that the risk is low is examined in this paper which details the technologies and components which comprise current, second generation design laser crosslinks. The specifics which are examined include diode power summing, diode life, data rates of a Gbps and beyond, detector sensitivity/radiation effects, telescopes, gimbals and optics, alignment stability, acquisition, pointing and tracking, electronics and the space qualification of assemblies and systems. Differences between first and current (second generation) system designs and technologies are examined. An assessment of the maturity of the current direct detection technology is made and conclusions formulated.