This chapter presents a review of the most relevant experimental results demonstrating the ability of nanosecond laser annealing to achieve dopant activation well above the solid solubility limit. Several distinctive materials science issues related to laser kinetics in the melt regime are reviewed, including melt temperature differences between amorphous and crystalline phases, melt front propagation, melt duration, recrystallization velocity, and solute trapping. Finally, the morphology, crystalline nature, and residual damage of Si, Ge, and SiGe materials submitted to nanosecond laser anneals in the melt regime are discussed according to the material fabrication history as well as the laser anneal conditions.Due to the richness and relevance of numerous seminal works published in the late 1970s–the early 1980s in this domain, the results reported in this chapter are mainly presented in the form of a historical review …