Mexico is a culturally, socially and economically heterogeneous country, with a population of over 100 million. Although it is regarded as a country with a medium–high income according to World Bank criteria, inequality continues to be one of its main problems. In addition to this, the country is going through a difficult period. Large parts of the population face economic insecurity, as a result of which feelings of despair, fear and impotence are common. It is hardly surprising, then, that mental disorders should constitute a major public health problem: depression is the main cause of loss of healthy years of life (6.4% of the population suffer from it), while alcohol misuse is the 9th (2.5%) and schizophrenia the 10th (2.1%) most common health problem (González-Pier et al, 2006).

The Mexican health system

The Mexican health system is divided into three types of service provision.

First, social security provides services for the formal, salaried sector of the economy and covers 47% of the population. This type of security guarantees free access to healthcare and is financed through contributions from both employers and employees.

Second, those not covered by social security (45% of the total Mexican population), who are also the poorest, were long regarded as a residual group, for whom the Health Secretariat provided a poorly defined benefits package. In 2000, the Popular Insurance Scheme was created to provide protection for this vulnerable population. The intention was to expand the coverage of this insurance only gradually. Two kinds of mental health service are included under this scheme: preventive medicine and external consultation services. Beneficiaries of the Popular Insurance Scheme are entitled to receive treatment for the diseases included in the Universal Catalogue of Essential Health Services (CAUSES), which covers all the medical services provided at primary health centres and associated medication. In relation to mental health, CAUSES include: attention deficit disorder, eating disorders, alcohol misuse, depression, psychosis, epilepsy, Parkinson's disease and convulsive crises.

Third, there is a heterogeneous group of private service providers who attend non-insured families who are able to afford them and the population which, despite having some form of social security, is dissatisfied with the quality of services; this group accounts for just 4% of the population (Frenk, 2007).