In the 1970s, Cuba made a major effort to assume a leadership role in the world's nonalignment movement, which represented over 90 Third World nations. Its combat troops in Angola greatly impressed fellow non-aligned nations. Cuba also established military advisory missions, and economic and social reform programs. Apart from interventions in revolutionary conflicts and civil wars, Cuba made world-wide commitments to social-and economic programs in 40 poor countries. This was made possible by the improved Cuban economy in the 1970s. The largest programs involved major construction projects, in which 8,000 Cubans provided technical advice, planning, and training of engineers. Educational programs involved 3,500 teachers. In addition thousands of specialists, technicians, and engineers were sent as advisors to agricultural mining and transportation sectors around the globe. Cuba hosted 10,000 foreign students, chiefly from Africa and Latin America, in health programs and technical schools. Cuba's extensive program of medical support to international attention. A 2007 study reported: