References can take various forms - letters of recommendation, school leaving certificates, other official documents - and can provide useful information as part of an au pair or host family profile.
References provide information about a person's performance, social skills, personal attitude and capabilities. Au pairs can upload references free of charge to their profiles. Host families need to have a Premium Membership in order to upload references and to read the references of au pairs. If you feel the need for more information about a possible au pairing partner, asking for references is a good step to take.
References for au pairs could be obtained from the present or a previous host family (if the au pair has previous au pairing experience). A teacher or employer of the au pair could also provide references, or a family where the au pair has worked as a babysitter. References for a host family could come from a previous or present au pairs that was hosted by the family the family, the teachers of the host family's children or the host parents' employers.
References may be provided in written form. However, it is also possible to directly speak with the persons who provide these references, should they agree to do so.
In addition to references, host families in particular, can ask their au pairs to provide a health or police clearance certificate. In some countries, au pairs need to submit their health certificate with their visa application.