The issue of adoptive families is the object of interest for many researchers, especially outside Polish borders. A critical analysis of previous studies on adoption shows that the scientific value of many of the existing studies raises many doubts. There is a little amount of studies on family systems. It seems worthy to note that numerous studies are conducted in the cause-effect model of explaining phenomena in the adoptive family. Discussed issues include: theoretical models, arrangement of studies, especially the selection of the test group and the research methods used in the study on adoptive families. Conducting scientific research is essential for the adoption practice. Among psychologists-practitioners exists a disturbing belief that working with adoptive families can be based on the experience gained in psychological practice. This fact can be explained by the existing lack of willingness of adoptive families to cooperate in the field of scientific research. Lack of this cooperation significantly limits the access to the study population of adoptive families.