The Pak-U.S. relations have been through many ups and downs throughout the history of Pakistan. For most of the time during the cold war, relations remained either warm or normal except for some short periods. The ties went down the slope after the cold war and towards the onset of the twenty-first century. In addition to some drastic shifts in the regional and global political scenario, the incident of 9/11 proved a watershed for Pak-U.S. ties as well. Pakistan's decision to stand with America and her allies provided an opportunity for both the states to improve bilateral ties. Key challenges include, but not limited to, issues of trust and coordination, the problems of strategic harmony and divergence of interests and varied policies about arms and nuclear proliferation. Pak-U.S. relations have also been affected by their respective relations with other states. From Pakistan's perspective, it is essential not only to identify points of convergence and divergence with the United States but also to explore policy options to meet such challenges.