and Perova, 2014). Our study contributes to this literature in two ways. First, we explored whether there is heterogeneity in benefits by gender using quantitative methods: we rigorously evaluated the genderspecific impacts of a large-scale road rehabilitation and maintenance project in Vietnam. As discussed in the introduction, we tested two hypotheses that have distinct policy implications. Women may benefit less than men from better roads if road improvements address only some of the constraints that women face (complementary constraints hypothesis). Women may benefit more than men from road rehabilitation if for an equivalent reduction in travel time the marginal value of their time is higher (tightness of constraint hypothesis). In the latter case, rural road improvements may on their own be an investment towards the Sustainable Development Goal (SDG) of gender equality. In the former case, complementary interventions may be needed to avoid exacerbating existing inequalities between the genders.

Second, we complement our quantitative analysis with qualitative data collection to provide additional insights into what barriers prevent one gender from taking full advantage of improved roads. The analysis is based on in-depth interviews and FGDs carried out in October and November 2018 with women and men living in three project sites.

The combined quantitative and qualitative results suggest that better roads expanded economic opportunities, particularly in agricultural production and trade. However, our results also indicate that male-headed households are significantly more likely to take advantage of these opportunities.

Increasing agricultural production and trade required an increase in usage of labor or machinery. Maleheaded households have one more working-age adult than female-headed households and are either able to increase the amount of labor on the farm or use the income from the extra adult to rent machinery. Female-headed households, suffering from a household labor deficit, are more constrained in increasing farm labor or renting machinery. Given the lack of efficient credit markets in our study areas, they are also not able to substitute capital for labor and borrow to make these investments. We find evidence of increased income from sales of assets among female-headed households—selling assets may be a strategy to access capital for agricultural investments.

Overall, our results point towards the validity of the complementary constraints hypotheses and suggest the need for complementary interventions to allow both genders to fully reap the potential benefits of better roads. This resonates with one of the main messages of a recent World Bank study on the Belt and Road Initiative, of which Vietnam is a part,<sup>22</sup> that complementary programs are required to “unlock” the full potential of investments in transport corridors not just to increase impacts and deepen inclusion, but also to mitigate their social and environmental risks <mark>(World Bank, 2019)</mark> .

In our study context, facilitating access to credit combined with financial literacy training and business development skills would be one example of such complementary intervention. The impact of such an

> 22 The upgrade to Vietnam’s NH-5 connecting Hanoi to Hai Phong port, carried out with Japanese aid, is highlighted as an example of a project where complementary policies, including investments in human capital and improvements in business environment, led to successful economic development along the corridor.

21