in material science and solid-state physics— though this research work was based on independent but authoritative and classified research sponsored by the British government. Career at Government of Pakistan Pakistan Atomic Energy Commission In 1961, Butt secured employment in the Pakistan Atomic Energy Commission (PAEC) as a scientific officer, and worked on the problems involved in reactor physics before departing to England for his doctoral studies. Upon returning in 1966, Butt joined the Fast Neutron Physics Group at the Institute of Nuclear Science and Technology in Nilore, where he conducted work on the neutron diffraction to understand crystalline arrangement in the atomic structure. His career is mostly spent at the Institute of Nuclear Science and Technology, the country national laboratory site in Nilore, where he was instrumental in conducting scientific investigations in solid-state materials using the lattice dynamical settings and powder diffraction techniques. Much of his scientific work at the national laboratory site remains classified in regards to its relation to the development of his nation's nuclear weapons. From 1966 to 1978, Butt engaged in further scientific understanding of the neutron, an important subatomic particle, and studied the utilization of the Pakistan Atomic Research Reactor with Neutron Activation Analysis . In 1978, Butt passed over his work in understanding neutron applications when he was appointed director of Nuclear Physics Division where he became interested in the nuclear binding energy in the nucleus, the isotopic island of stability, phonon and the Mössbauer effect. While leading the Nuclear Physics Division, Butt oversaw the establishment of the "New Labs" where many of his contributions were vital in scientific understanding in synthetic elements such as plutonium 93Pu. In 1984, Butt was appointed as associate director of the Institute of Nuclear Science and Technology, and promoted to its director in 1991. In 1995, he eventually took over the Institute of Nuclear Science and Technology as its director-general, but left the directorship for a chief scientist position in 1996. In 1998, Butt was part of a small team that eye-witnessed the nuclear chain reaction during the atomic tests in the mountains of Balochistan in Pakistan. In 1999, he was of the opinion to favor the development of the less destructive neutron bomb as opposed to the much larger blast radius guaranteed by the hydrogen-based design of nuclear weapons. In 1999, Butt eventually left the Institute of Nuclear Science and Technology when he retired as first "Scientist