NON-TECHNICAL SUMMARY Shape memory alloys (SMAs) experience reversible transformations, shifting back and forth between different arrangements of atoms, which in term dictate their properties. Once stretched, they undergo a change and then upon removal of the load, they can return to their original shape. Such a phenomenon finds applications in cardiovascular stents, structural dissipation under impacts, and actuators for motion control. Consequently, these kinds of materials can be used in defense, healthcare, aerospace, and structural engineering. However, for these materials to be trusted as reliable, they need to function over many cycles. However, the inability to return to its original shape is termed an “irreversibility”. Irreversibilities can eventually result in fatigue cracks, compromised performance and reduced durability. This work focuses on improving the understanding of atomic level changes in shape memory alloys such as NiTi and NiMnTi. The aim is to mitigate these irreversibilities via changes to elemental composition, introducing precipitates, and modifying atomic arrangements to reduce the defects that lead to irreversibilities. The introduction of precipitates in these materials is particularly promising, as they have been shown to facilitate transformation, imparting additional reversible strains especially under high stress applications. In this proposal, the advances in science-based understanding of SMA interfaces is establishing high-accuracy resul