Cardiopulmonary resuscitation (CPR) is a well-established part of basic life support (BLS), saving countless lives since its first development in the 1960s. Recently, work has been undertaken to develop methods of basic and advanced life support (ALS) in microgravity and hypogravity. Although the likelihood of a dangerous cardiac event occurring during space mission is rare, the possibility exists. The selection process for space missions nowadays considers individuals at ages and with health standards that would have precluded their selection in the past. The advent of space tourism may even enhance this possibility. This chapter presents a synthesis of the results obtained in studies conducted at the MicroG-PUCRS, Brazil, examining extraterrestrial CPR during ground-based microgravity and hypogravity simulations and during parabolic flights and sustained microgravity. It outlines the extraterrestrial BLS guidelines for both low-orbit and deepspace missions. The former are based on a combination of factors, unique for the environment of space. In a setting like this, increased physiological stress due to gravitational adaptation and the isolated nature of the environmental demands can affect the outcome of resuscitation procedure.