In a short time, Spanish Legal Psychology has gone from the purest ostracism to being at the forefront of research worldwide. During the dictatorship, it was subjected to a period of forced silence and it is from the 1980s when it resurfaces under the guidance of Muñoz-Sabaté, and in the 1990s it is consolidated under the guidance of world renowned researchers such as Vicente Garrido, Santiago Redondo, Ramón Arce, Francisca ^{Fariña, Jorge Sobral or Antonio Andrés-Pueyo (Fariña et al., 2005}). Research in violence, especially in youth and gender violence, has generated a corpus of research that has culminated in very remarkable theoretical advances (e.g., two-way model in child-to-parent violence, and in knowledge transfer for practice, i.e. applications based on scientific evidence -e.g., intervention programs with abusers in the community; VioGen). Thus, a recent meta-analysis has shown that in intervention with batterers it is the reference in sentenced to treatment, especially in the community, but also of sex offenders and in crime in general (^{Arce et al., 2020}). Likewise, global research with both community, judicial and clinical populations in child-to-parent violence is mainly Spanish as it includes a recent meta-analysis (^{Gallego et al., 2010}). No less important is the risk assessment of violent behavior and recidivism. It is for all these reasons that this monographic issue captures new advances of these groups in their fields of work. In this way, this monograph includes new contributions in the epidemiology in gender-based violence (contrast of inter-country variability) and the study of the true probability (corrected by concealment) of child-to-parent violence; study of the role of gender as a moderating variable in assessing the risk of child-to-parent violence; assessment of the effectiveness of cognitive behavioral treatment to batterers in the community in cognitive skills (recidivism measures are not valid by not detecting most of them) quantifying achievements in each of the markers of cognitive skills, as well as in each case; an evaluation of the intervention in the community of batterers in proximal (intention of change, assumption of responsibility, adherence to treatment and commitment to intervention) and final (recidivism) measures; and a field study showing that non-criminogenic needs arising from individual, social and psychological adjustment are a risk factor for criminal behaviour and that, therefore, contrary to what is predicted in the R.N-R model, they must be subject to intervention. From all of them, advances are derived both in theory at the level of models and for professional practice based on scientific evidence.