In mid-1977 and again in early 1978, the “2nd Army,” now heavily rearmed by Libya, launched a series of devastating attacks against CSM positions in Chad’s northern territories. After a series of failed negotiation efforts on the part of the CSM, rebel moves in the direction of N’Djamena led French President Valéry Giscard d'Estaing to order a military intervention. Operation Tacaud aimed to protect the capital and the (comparatively) economically prosperous Chadian south from apparent Libyan designs. This chapter examines French diplomatic and military efforts to stabilize Chad in 1977 and 1978, and the policymaking process behind Giscard's decision to intervene on behalf of the CSM. It also looks at the negotiations that led Hissène Habré, who had broken with Goukouni in 1976, to agree to join a coalition government headed by Malloum and supported by France.