# 1 Introduction

International migration is a diverse phenomenon and its impact on source and destination countries has attracted increased attention of policymakers, scientists and international agencies. The migration pressure has increased over the last years and is expected to intensify in the coming decades given the rising gap in wages and the di¤ering demographic futures in developed and developing countries. Understanding and measuring the consequences for migrants, host countries’residents and those left behind is a major and di¢ cult task. In particular, the impact of the brain drain on sending countries results from a complex combination of direct and feedback e¤ects which are extremely di¢ cult to quantify.

Due to the lack of harmonized data, the brain drain debate has, until recently, remained essentially theoretical<sup>1</sup> . New data sets have been developed to assess the magnitude of the brain drain. In particular, Docquier and Marfouk (2006)<sup>2</sup> provided estimates of emigration stocks and rates by educational attainment for 195 source countries in 2000 and 174 countries in 1990. This data set gave rise to a couple of extensions as well as to a number of empirical studies on the determinants and consequences of the brain drain<sup>3</sup> .

One important extension which has been strongly disregarded in the literature concerns the gender gap in international migration. In particular, little research has addressed the issue of female migration while a considerable strand of literature has focused attention on male migration. The share of women in international migration increased over the last decades. According to the United Nations, this share increased from 46.8 to 49.6 percent between 1960 and 2005. This evolution is mostly due to the rising representation of women in the immigration stock of the most advanced countries (from 48.9 to 52.2 percent)<sup>4</sup> . It results from many factors such as the rise in women’s educational attainment, the increased demand for women’s labor in health care sectors and other services, or cultural and social changes in the attitude towards female migration in many source countries. Although family reunion programs admit many women in destination countries, women cannot be considered as passive companion migrants. The feminization of international migration raises speci...c economic issues related to the gendered determinants and consequences of migration. In particular, women’s brain drain is likely to a¤ect sending countries in a very peculiar way.

First of all, women’s level of schooling is a fundamental ingredient for growth. Many studies demonstrate that women’s education complements children’s investments in school and has important e¤ects on the human capital of future generations

> 1See Commander et al. (2004) or Docquier and Rapoport (2007) for literature surveys.

> 2Henceforth, DM06.

> 3See Docquier et al. (2007), Beine et al. (2007b), Cecchi et al. (2007), Krueger and Rapoport (2006), Nimii and Ozden (2006), Javorcik et al. (2006), Grogger and Hanson (2007), Easterly and Nyarko (2005), etc.

> 4In developing countries, the share of women has been relatively stable over time.

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