What resources are needed? This has two potential benefits. It ensures that training has strong practical foundations, and it continually exposes service providers to new thinking and development. In countries with large rural populations several strategies have been used to recruit staff to rural areas Examples are intake of medical students from rural areas and training in the locations Arelated problem concerns the brain drain of trained staff from low income countries to wealthier countries or from the public sector to the private sector within a country. The more successful trainees often emigrate, tempted by higher standards of practice and living abroad. Many Jamaican nurses have migrated to the United States. Physicians migrate from Egypt and India to other countries in the Middle East and to the USA and Europe Inadequate pay and benefits rank as the most serious problem confronting the public sec- tor health workforce in many countries, with growing formal and informal private practice as a consequence. Service contracts that require a certain number of years in public service, especially when the training is state sponsored, have been implemented in the Philippine and the United Republic of Tanzania, and are common in Latin America but there are attendant difficulties. The staff concerned are usually junior, placements are short term and unpopular, mentoring arrangements are seldom adequate, and overall geographical im balance is little affected. Globalization has led to greater mobility of staff and opportunity for overseas training, and students who qualify abroad may wish to stay in the coun here they were trained ADJUSTING TO ADVANCES IN KNOWLEDGE AND TECHNOLOGY Growth in the available knowledge or advances in technology- such as new drugs or diagnostic equipment-can substantially increase the capacity of human resources to solve health problems, and thereby improve the performance of a health care system. New knowl dge is also a challenge to each countrys existing input balance, as relative prices chang and the efficient mix of resources alters (9). In the past few decades, revolutionary advances in medicine and technology have shifted the boundaries between hospitals, primary health care, and community care (10). Corresponding resource shifts in health systems have been much slower to emerge. Antibiotic drugs provide one example of new knowledge affecting cost structures. Since their introduction in the 1940s, patients suffering from a bacterial infection have most often been cared for at home or at outpatient clinics rather than in special hospitals, significantly reducing costs and improving outcomes. The recent growth of unregulated self-treatment and the increasing incidence of drug-resistant bacteria have compromised some of these gains. There is now a need for active stewardship to regulate the quality of diagnosis, pre- scribing and compliance. Vaccines have similarly altered the strategy and costs of tackling epidemic diseases such as measles and poliomyelitis, and new vaccines will continue to necessitate re-thinking to ensure an efficient mix of inputs in national health strategy All countries-nich as well as poor-need to find and maintain a reasonable balance tween inputs. The choices involved in finding this balance, however, vary depending on the amount of total resources available. In a poor country, the possibilities of investing in modern medical technologies or paying for modern medicines are very limited. Moving from the use of essential drugs to new and expensive dru would mean an enormous opportunity loss in terms of health outcome for a poor country. This difference in opportunities across countries also has an impact on the optimal balanceWhat Resources are Needed? 81 This has two potential benefits. It ensures that training has strong practical foundations, and it continually exposes service providers to new thinking and development. In countries with large rural populations several strategies have been used to recruit staff to rural areas. Examples are intake of medical students from rural areas and training in the locations where physicians will later practise. A related problem concerns the brain drain of trained staff from low income countries to wealthier countries or from the public sector to the private sector within a country. The more successful trainees often emigrate, tempted by higher standards of practice and living abroad. Many Jamaican nurses have migrated to the United States. Physicians migrate from Egypt and India to other countries in the Middle East and to the USA and Europe. Inadequate pay and benefits rank as the most serious problem confronting the public sec￾tor health workforce in many countries, with growing formal and informal private practice as a consequence. Service contracts that require a certain number of years in public service, especially when the training is state sponsored, have been implemented in the Philippines and the United Republic of Tanzania, and are common in Latin America but there are attendant difficulties. The staff concerned are usually junior, placements are short term and unpopular, mentoring arrangements are seldom adequate, and overall geographical im￾balance is little affected. Globalization has led to greater mobility of staff and opportunity for overseas training, and students who qualify abroad may wish to stay in the country where they were trained. ADJUSTING TO ADVANCES IN KNOWLEDGE AND TECHNOLOGY Growth in the available knowledge or advances in technology – such as new drugs or diagnostic equipment – can substantially increase the capacity of human resources to solve health problems, and thereby improve the performance of a health care system. New knowl￾edge is also a challenge to each country’s existing input balance, as relative prices change and the efficient mix of resources alters (9). In the past few decades, revolutionary advances in medicine and technology have shifted the boundaries between hospitals, primary health care, and community care (10). Corresponding resource shifts in health systems have been much slower to emerge. Antibiotic drugs provide one example of new knowledge affecting cost structures. Since their introduction in the 1940s, patients suffering from a bacterial infection have most often been cared for at home or at outpatient clinics rather than in special hospitals, significantly reducing costs and improving outcomes. The recent growth of unregulated self-treatment and the increasing incidence of drug-resistant bacteria have compromised some of these gains. There is now a need for active stewardship to regulate the quality of diagnosis, pre￾scribing and compliance. Vaccines have similarly altered the strategy and costs of tackling epidemic diseases such as measles and poliomyelitis, and new vaccines will continue to necessitate re-thinking to ensure an efficient mix of inputs in national health strategy. All countries – rich as well as poor – need to find and maintain a reasonable balance between inputs. The choices involved in finding this balance, however, vary depending on the amount of total resources available. In a poor country, the possibilities of investing in modern medical technologies or paying for modern medicines are very limited. Moving from the use of essential drugs to new and expensive drugs for cardiovascular diseases would mean an enormous opportunity loss in terms of health outcome for a poor country. This difference in opportunities across countries also has an impact on the optimal balance