Background. Nonviolent Communication© (NVC) was developed by Dr. Marshall B. Rosenberg to foster intra and interpersonal relationships of compassion, collaboration and caring. It has been applied in a variety of settings like schools, hospitals, prisons and in restorative justice systems. Even though NVC as it is today has emerged out of research since the 1960s, studies into the impact of the model started only in the 1990s (Steckal, 1994). This systematic review intends to assess the research done up until now about NVC and its findings concerning empathy development.

Methodology. Electronic databases (mainly ERIC, PsychINFO and ASSIA) and an active consultation with experts were undertaken in search for papers, reports and theses, in any language, reporting empirical studies on NVC.

Results. From 2634 citations, fourteen studies were identified, citing thirteen experiments, which complied with the inclusion criteria. These studies present heterogeneity of methods and measures, meaning it was impossible to realize a meta-analysis. Eight of these studies evaluated the results of purposive workshops, and five assessed the impact of NVC in real-life situations. All of these five were conducted in educational institutions. Only two studies coincide in the use of two validated measures. The remainder of the studies use other measures and researcher made instruments. Non-randomized selection of participants, lack of reporting and small number of participants, are the main shortcomings observed in the studies.
The results regarding empathy development are positive in all studies except two. Other positive outcomes relate to increase of communication skills, betterment of relationships, fewer conflicts as well as new conceptions and ways to handle them.

Conclusion. The promising results regarding the efficiency of NVC on empathy development, among other outcomes, would need to be confirmed with further studies bearing stronger designs and more appropriate measures. A limitation patent in the studies included, which is shared with other reviews on the subject (Butters, 2010; Lam et al., 2011 and Stepien & Baernstein, 2006), is the mismatch between the constructs of the model and the validated empathy measures, developed in the 1980s. New updated instruments, like the one developed by Steckal (1994), need to be created and validated in order to evaluate the specificity of the NVC model.