In this category, notarial involvement is possible and necessary in many cases, such as the following examples:

Family relations, adoption, guardianship, and disabilities:

A child can be acknowledged in a will or in a notarial deed.

In the case of international adoption, all required documentation must be notarized.

Through a public deed, parents can emancipate their children over the age of 16, allowing them to manage their own person and property as if they were of legal age. However, they cannot, among other things, take out loans or sell real estate without parental authorization.

Minors can be authorized by a notarial deed to engage in certain activities, such as traveling abroad with someone other than their parents.

In cases of donations or wills where assets are freely given to children, rules for the administration of these assets can be established.

Rules of "self-guardianship" can be set in a public deed, clarifying many aspects of future guardianship for children if necessary. A protected estate can also be created for individuals with disabilities, providing security and organizing their finances with significant tax benefits.

Marital and non-marital relationships:

A notarial deed for prenuptial agreements regulates the economic regime of a marriage, which can be done during the marriage or in the year prior to it.

If no regime is agreed upon, the legal default is the community property regime for regions under common law (all of Spain except Álava, Aragón, Balearic Islands, the territory of the Fuero de Baylío, Catalonia, Galicia, Guipúzcoa, Navarra, Vizcaya, and the Valencian Community) or as determined by the specific legislation of these regions.

Notarial deeds can also prove the certainty of situations such as de facto separation and regulate its effects.

Public deeds can be used to agree on personal and property relations of common-law unions, as well as the consequences of their dissolution.

Powers of Attorney:

A widely used notarial document that allows one person, whether an individual or legal entity, to represent another in any act (general power of attorney) or in specific acts listed in the deed (special power of attorney). The revocation of these powers must also be done by public deed.