Placement in kinship family has existed informally throughout time. There are many countries in which kinship family care is the most common measure used for child protection. However, it is a subject of continuous debate. One of the major issues is that kinship foster care is relied upon without carrying out an evaluation study of the family; often the child is placed directly with grandparents and uncles simply because they are direct family. This article presents an assessment tool to evaluate extended families in order to ensure the welfare of the child. The tool was created as a result of the cooperative research of 126 professionals from seven regions of Spain. The tool can identify the strengths and weaknesses of families by considering six factors: personal characteristics, the coverage of basic needs, collaboration with professionals, the family structure and dynamics, the relationship between family, child, and biological family, and, finally, the attitude towards the placement. The assessment tool is innovative and introduces the opportunity to consider the skills of the kinship foster care family, the needs of support, and which families are unfit to take care of the child. To conclude, the tool tries to overcome one of the principal disadvantages of kinship foster care: the lack of knowledge about the kinship family.