Nitinol presents a compelling alternative to conventional actuation systems. Its unique shape memory effect (SME), combined with a high force-to-mass ratio, low stiffness, and high corrosion resistance, makes it particularly attractive for aerospace and automotive applications. In contrast, conventional actuation systems such as pneumatic or hydraulic systems are bulky, heavy, requiring assembly and regular maintenance. Nitinol can enable compact, single component solutions that provide silent actuation, lower energy consumption, reduced weight, and minimal maintenance. Conventionally manufactured nitinol benefits from an established supply chain and reliable processing routes, with wires being among the most common forms. The thermomechanical processing of these wires introduces complex microstructural features that require careful post processing treatments to achieve desired functional properties. Chapter 3 reveals that heat treating NiTi wires between 400 °C and 500 °C results in a decrease of over 18 °C in the transformation temperatures owing to the precipitation of secondary phases. Chapter 4 shows that stroke of a NiTi wire actuator is increased by up to 230 % when aging temperature is increased from 350 °C to 450 °C. A key limitation of traditionally manufactured nitinol is its poor machinability, which restricts components to simple geometries such as wires, coils, and sheets. This constraint has driven increasing interest into the additive manufacturing (AM) of nitinol. Techniques such as laser powder bed fusion (PBF-LB) allow the fabrication of complex geometries not previously possible as well as providing the opportunity to tailor microstructural and mechanical properties by optimizing processing parameters. Chapter 5 demonstrates that relative densities of 99.4 % can be achieved at VEDs of 42 J/mm3 while chapter 6 demonstrates that stroke increases by 11.9 % when VED is decreased from 83 J/mm3 to 21 J/mm3 in PBF-LB lattice structures. A significant gap remains in the literature concerning the effects of conventional and AM processing on the thermo-mechanical response of nitinol. This thesis focuses on filling this gap in knowledge. The effect of PBF-LB process parameters on the material properties of 2 martensitic nitinol and its shape memory response are evaluated and presented. By gaining a deeper understanding of how PBF-LB process parameters influence the final properties of nitinol actuators, it becomes more possible to engineer light-weight, low-maintenance actuators capable of replacing traditional actuation systems. Actuators are integral to countless systems, and such advancements could significantly reduce energy and fuel consumption during both the manufacture and operational lifetime particularly of critical industrial, aerospace, bioengineering, and automotive actuators.