670 HUMAN RIGHTS QUARTERLY Vol. 39 agreed-upon development goals, address key social issues, or indeed fulfil the welfare basket.54 While the importance attributed to human capital as a requirement for healthy social systems is by no means controversial,55 it may still seem that, in an assessment of a duty-bearer’s maximum available resources, its presence as an additional variable is superfluous. Instead, it could be argued that the availability of financial resources instrumentally captures the duty-bearer’s ability to provide human resources; the more financial resources it has the more teachers, doctors, nurses, and engineers it is able to recruit, train, and employ.56 In a perfectly operating market for professional workers, this would indeed be the case; a measure of available financial resources would be a good enough proxy. However, the market for professional workers is far from perfect. In the arena of health alone, there is an estimated worldwide shortage of almost 4.3 million doctors, midwives, nurses, and support workers, and this shortage is felt most acutely in countries where these professional workers are needed most:57 a situation that has been described by the World Health Organization as a “global crisis.”58 An understanding of the factors that contribute to the shortage is important for explaining maximum available resources. The shortage may be due to, for instance, increasing social needs or that the economic and social incentives to train, work, and live as a professional in certain countries are simply not sufficiently strong, often resulting in migration from already resource poor countries to more resource abundant countries, coined the brain drain/brain gain.59 In each of these cases, or indeed a mixture of both, it would be unrealistic to assume that a duty-bearer’s ability to fulfill the welfare basket is a matter of money alone. If a duty-bearer has the financial resources to provide access to certain social goods and services (which in principle could satisfy fulfillment of the welfare basket) yet, despite employing the maximum human resources it has available, there are still too few professional workers of the appropriate kind to deliver those goods and services, then it cannot necessarily be expected to fully deliver them in the 54. Hugo Mercer, et al., Human Resources for Health: Developing Policy Options for Change, in Towards a Global Health Workforce Strategy 451 (Paulo Ferrinho & Mário Dal Poz eds., 2003). 55. See the vast portfolio of documents on human resources development and social rights published by the Office of ECOSOC Support and Coordination, available at https://www. un.org/ecosoc/en/node/454160. 56. Sakiko Fukuda-Parr, Terra Lawson-Remer, & Susan Randolph, An Index of Economic and Social Rights Fulfillment: Concept and Methodology, 8 J. Hum. Rts. 195 (2009). 57. World Health Organization, The World Health Report 2006: Working Together for Health 12 (2006). 58. World Health Organization, Human Resource for Health: Overcoming the Crisis 18 (2004). 59. Id. at 101.