Heat pumps are one of the most promising technologies for residential and industrial applications in the perspective of a decarbonized society. Their role in climate change mitigation can be fully capitalized through their direct coupling with renewable energy sources, among which solar heat is the most abundant one. The systems that feature the integration of heat pumps and solar systems are known as solar-assisted heat pumps. In the present chapter, the fundamentals of mechanical compression and sorption heat pumps are given and their utilization in combination with solar thermal collectors is discussed, highlighting the relevant features of each possible layout according to the expected useful effect and field of application, showing that heat pumping technology has a central role in the reduction of emissions due to heating and cooling production.