Nitrogen is one of the elements essential for life as we know it and is also a key constituent of some of the gases that provide warming and cooling effects on planetary surfaces. However, how nitrogen is acquired and processed during the formation and differentiation of rocky planets is poorly known. To gain insights into the fate of nitrogen through various stages of rocky planets' formation, such as core formation, magma ocean outgassing, and crystallization, partial melting of planetary mantles, and core crystallization, here I will present high-pressure-temperature laboratory experimental data on nitrogen solubility and partitioning acquired in our laboratory over the last few years and ongoing efforts. The main constraints that will be presented and discussed are (a) nitrogen partitioning during metal melt-silicate melt differentiation, (b) nitrogen solubility in silicate melts, (c) nitrogen partitioning between silicate minerals and metallic/sulfide-rich melts, (d) nitrogen partitioning between silicate minerals and silicate melts, and (e) nitrogen partitioning between solid and liquid metals. The key variables that are explored, include pressure, temperature, oxygen fugacity, metal melt compositions including the concentrations of other non-metals, silicate melt compositions, and silicate mineralogy. I will present an advancement in the understanding of nitrogen distribution in the main planetary reservoirs. I will also discuss what differentiation conditions potentially facilitate the formation of nitrogen-rich atmospheres such as that on Earth.