Becoming the third largest metropolis of the United States, Houston has become a gateway to the Americas, particularly in connection to trade, finance, health, aerospace, and energy markets. It also is an international and port city with important interests in environmental resilience and technological innovation to support its varied business sector. It is a center for trade and international affairs, hosting broad consular corps that serve the entire region. More than 145 languages are spoken in this ethnically and racially diverse metropolis, attracting international business and foreign investment. The University of Houston Law Center also hosts many international students and has an extensive Global Alumni Network.