Jack B. Zirker donned the robes of astronomer emeritus on 1 January 1996. In addition to his prominent scientific career, Jack played a pivotal role in the evolution of the solar facilities on Sacramento Peak and in the formation of the National Solar Observatory. Jack first came to Sunspot in 1954 as a summer student. He received his PhD from Harvard in 1956 for investigations in collaboration with R.N. Thomas and R.G. Athay on the temperature structure of the chromospheres and lower corona derived from non-LTE analysis. During the years 1956-1964 at Sacramento Peak, Jack's work included elucidating the properties of photospheric filigree, a fine-scale magnetic structure discovered by R.B. Dunn. Between 1964 and 1976, Zirker was a professor at the University of Hawaii and participated in the development of Mauna Kea as an observing site. Jack returned to Sunspot in 1976 to assume the directorship of the Sacramento Peak Observatory, which had just been transferred from the US Air Force to the National Science Foundation. His leadership was strongly felt during those years of transition and re-orientation. In the early 1980s, Jack was instrumental in the formation of the National Solar Observatory as a consolidation of SPO with the solar section of the Kitt Peak National Observatory and, shortly thereafter, as a division of NOAO. Jack Zirker's broad scientific interests are reflected in over a hundred scientific papers and several books, including a well-known monograph on solar eclipses and a recently-completed biography of Robert Dicke. His research has included mechanisms of coronal heating, the physics of prominences and their fine structure, flare mechanisms and energy distribution, and the use of non-redundant arrays for high-resolution imaging.