However, this positive effect is limited by the small amount of attention which GHPs have dedicated to strengthening national health systems, and by the unintended adverse impact that they may have on those systems, as discussed below. In addition, the provision of services does not reflect the actual use of those services by different sectors of society. There is ample evidence that improvements in access to antiretroviral treatments in Africa, for example, do not necessarily lead to the actual use of those treatments by many people, especially among the poor. To achieve this requires strengthening national structures of primary health care, aiming at providing rational, evidence-based and anticipatory responses to health needs and to social expectations.