Local legislation may regulate the operation of daycare centers, affecting staffing requirements. Laws may mandate staffing ratios (for example 6 weeks to 12 months, 1:4; 12 months to 18 months, 1:5; 18 months to 24 months, 1:9; et and even higher ratios for older children). Legislation may mandate qualifications of supervisors. Staff typically do not require any qualifications but staff under the age of eighteen may require supervision. Typically, once the child reaches the age of twelve, they are no longer covered by daycare legislation and programs for older children may not be regulated.
Spain provides paid maternity leave of 16 weeks with 30-50% of mothers returning to work (most full-time) after this, thus babies 4 months of age tend to be placed in daycare centers. Adult-infant ratios are about 1:7-8 first year and 1:16-18 second year. Public preschool education is provided for most children aged 3–5 years in "Infantil" schools which also provide primary school education.