Additive manufacturing has revolutionized parts manufacturing, but it is not without its challenges, which include microstructure defects that can compromise the mechanical properties. This study provides valuable insight on how the LENS technique can be applied to the fabrication and repairing of existing 17-4 PH stainless-steel parts. An optimisation procedure aimed at ensuring the quality of the produced parts was conducted to evaluate the effects of processing parameters. Thin-walled coupons were constructed to determine the influence of processing parameters on build height and physical integrity. It was observed that the build height decreased with an increase in scanning speed. Subsequently, cubic test coupons were manufactured to investigate the influence of a change in dimensions and to identify factors that contributed towards achieving dense samples. It was observed that an increase in scanning speed contributed to the formation of porosity, while reduced speeds and increased energy inputs ensured sufficient laser-powder interaction for improved melting. Accordingly, a high degree of densification was achieved (99.9%) with an energy density of 273J/mm3. The dense samples were subjected to heat treatment under various conditions. This resulted in an increase in microhardness and tensile properties due to the presence of copper precipitates and a recrystallised microstructure produced.