Scientific literature has evidenced that some social work practices and research tend to foster assimilation and silence ethnic minorities. In the case of Roma, previous research has shown that many social welfare practices do not consider their voices and end up in actions for surveillance and control over social transformation. However, the successful practices in social work with the Roma population that overcome these limitations remain underexplored. This work contributes to this gap in the scientific literature by uncovering one key criterion of some successful actions in this regard. Through the communicative methodology, six women’s focus groups and 30 life stories were conducted. In total, this included 47 Roma women and 33 Roma men from three different Spanish regions, as well as interviews with 30 professionals from education, social services, and civic organizations. The results from the studied context present evidence of a main successful criterion in some social work practices: the inclusion of scientific evidence in the intervention with co-creation with the end-users through egalitarian dialogue. That is, in this context, through the use of scientific evidence together with the co-creation process, the results were very positive.