Magnetic-shaped memory materials have gained much attention from researchers and engineers alike. They have undergone extensive exploration for their plenty of applications in different domains. In the field of sensors, their sensitivity to magnetic fields allows accurate detection mechanisms, advancing industries reliant on precise measurement and monitoring. Additionally, their ability to perform reversible changes in shape under magnetic fields provides them with applications in actuation technologies, robotics, and aerospace. In refrigeration, magnetic shape memory materials present a sustainable alternative to conventional refrigerants via their capacity to absorb and release heat under an external magnetic field. These materials might contribute to renewable energies by converting waste heat into usable electricity with their potential application in thermoelectric modules and generators. Among these materials, Heusler alloys have been widely studied in different compositions and shapes since Fritz Heusler discovered them in 1903. There are two categories of Heuslers: half-Heusler compounds with the formula XYZ and full-Heusler compounds, which are ternary intermetallics of stoichiometric composition type X2YZ, where X and Y are transition metals, and Z is an element from columns III, IV, or V of the periodic table. Heusler alloys can exhibit various properties, such as semi-conductors, semi-metals, or superconductors, and can exist in an austenitic phase, a martensitic phase, or a mixture of both phases. Austenite is a high-temperature phase that can be \({L2}_{1}\) or \(B2\) structure. However, martensite is a low-temperature phase of \({L1}_{0}\) , \(14\text{M}\) , or \(10\text{M}\) structure. Passing from austenite to martensite is guaranteed by a diffusionless structural transition by applying an external magnetic field, pressure, or temperature. These types of alloys are renowned for their sharp properties, including barocaloric effect, metamagnetic properties, magnetoresistance effect, thermomagnetic properties, magnetocaloric effect, and thermoelectric applications. Besides, we should shed light on the enhanced mechanical and thermal properties of the half-Heusler alloys. They exhibit high electrical conductivity and narrow band gaps. This chapter is devoted to providing prevalent research on the efficient applications in refrigeration and harvesting waste heat for some full and half Heusler alloys.